Crossroads between peripheral atherosclerosis, western-type diet and skeletal muscle pathophysiology: emphasis on apolipoprotein E deficiency and peripheral arterial disease

Association of Abdominal Aortic Calcification and Clinical Outcomes in LDH Patients Treated with Endoscopic Lumbar Discectomy

INTRODUCTION

To determine any significant associations between abdominal aortic calcification (AAC) and clinical manifestations of pain symptoms following endoscopic lumbar discectomy.

METHODS

Patients sequentially presenting with a history of unilateral radiculopathy with or without back pain, and with magnetic resonance imaging (MRI)-confirmed diagnosis of posterolateral disc herniation between August 2021 and December 2023 were eligible for inclusion in the study. All patients underwent endoscopic discectomy at our center during the study period. AAC stages were classified based on the Kauppila classification system using lateral lumbar radiographs.

RESULTS

Between August 2021 and December 2023 a total of 120 patients were included in the study for analysis, of whom 82 (68.3%) exhibited mild AAC and 38 (31.7%) had moderate-severe AAC. Analyses using the multivariate linear regression model revealed a significant correlation between AAC comorbidity and postoperative clinical outcomes. At 1 year post-surgery, the mean change in leg pain following endoscopic lumbar discectomy was significantly less for patients with moderate-severe AAC (5.0 points) than for patients with mild ACC (p < 0.001). Even after adjusting for relevant confounders, this difference remained significant. Similar results were also observed in the postoperative improvement of back pain, the Oswestry Disability Index score, and the physical functioning, role physical, and bodily pain components of the 36-item Short Form Health Survey questionnaire. There was no significant difference in the rate of repeat surgery or post-surgical new-onset back pain between patients with different levels of severity of AAC at 1 year post-surgery.

CONCLUSIONS

There is a significant association between the severity of AAC and clinical outcomes among patients with lumbar disk herniation who underwent endoscopic lumbar discectomy. AAC may serve as a prognostic factor in predicting surgical outcomes and guiding management strategies for patients with lumbar disk herniation following endoscopic lumbar discectomy.

The role of oxidative stress in intervertebral disc degeneration: Mechanisms and therapeutic implications

Oxidative stress is one of the main driving mechanisms of intervertebral disc degeneration(IDD). Oxidative stress has been associated with inflammation in the intervertebral disc, cellular senescence, autophagy, and epigenetics of intervertebral disc cells. It and the above pathological mechanisms are closely linked through the common hub reactive oxygen species(ROS), and promote each other in the process of disc degeneration and promote the development of the disease. This reveals the important role of oxidative stress in the process of IDD, and the importance and great potential of IDD therapy targeting oxidative stress. The efficacy of traditional therapy is unstable or cannot be maintained. In recent years, due to the rise of materials science, many bioactive functional materials have been applied in the treatment of IDD, and through the combination with traditional drugs, satisfactory efficacy has been achieved. At present, the research review of antioxidant bioactive materials in the treatment of IDD is not complete. Based on the existing studies, the mechanism of oxidative stress in IDD and the common antioxidant therapy were summarized in this paper, and the strategies based on emerging bioactive materials were reviewed.

Inhibition of SPARC signal by aerobic exercise to ameliorate atherosclerosis

BACKGROUND AND AIMS

Inflammation and atherosclerosis (AS) are closely associated to Secreted Protein Acidic and Rich in Cysteine (SPARC) and its related factors. This study attempted to define the role and the potential mechanism of SPARC and its related factors in ameliorating hyperlipidemia and AS by aerobic exercise intervention.

METHODS

The AS rat model was established with a high-fat diet plus vitamin D3 intraperitoneal injection. Treadmill exercises training (5 days/week at 14 m/min for 60 min/day) for 6 weeks was carried out for AS rat intervention method. Western blotting and qRT-PCR were used to analyze the mRNA and protein expression of SPARC and its related factors, respectively. H&E staining was applied to evaluate the morphological changes and inflammation damage. Von Kossa staining was used to measure the degree of vascular calcification. Fluorescence immunohistochemistry staining was used to detect the expression and distribution of SPARC signal molecules.

RESULTS

SPARC was highly expressed and co-localization with the smooth muscle marker α-SMC in the AS rat. And its downstream factors, NF-κB, Caspase-1, IL-1β and IL-18 were upregulated (P < 0.05 or P < 0.01), FNDC5 expression was downregulated in AS rat model. However, slight declined body weight, delayed AS progression, decreased hyperlipidemia and favorable morphology of skeletal muscle and blood vessels have been detected in AS rat with aerobic exercise intervention. Moreover, the expression of SPARC and its downstream factors were decreased (P < 0.05 or P < 0.01), while elevated the expression of FNDC5 (P < 0.01) was observed after aerobic exercise intervention.

CONCLUSIONS

This study suggested that aerobic exercise ameliorated hyperlipidemia and AS by effectively inhibiting SPARC signal, and vascular smooth muscle cells may contribute greatly to the protection of AS.

Association of abdominal aortic calcification and lower back pain in patients with degenerative spondylolisthesis

ABSTRACT

Abdominal aortic calcification (AAC) is hypothesized to lead to ischemic pain of the lower back. This retrospective study aims to identify the relationship between AAC and lower back pain (LBP) in patients with degenerative lumbar spondylolisthesis. Lower back pain was assessed preoperatively and 2 years after surgery using the numeric analogue scale. Abdominal aortic calcification was assessed according to the Kauppila classification and was grouped into no, moderate, and severe. A multivariable regression, adjusted for age, sex, body mass index, hypertension, and smoking status, was used to assess the association between AAC and preoperative/postoperative LBP as well as change in LBP after surgery. A total of 262 patients were included in the final analysis. The multivariable logistic regression demonstrated an increased odds ratio (OR) for preoperative LBP ≥ 4 numeric analogue scale (OR = 9.49, 95% confidence interval [CI]: 2.71-40.59, P < 0.001) and postoperative LBP ≥ 4 (OR = 1.72, 95% CI: 0.92-3.21, P = 0.008) in patients with severe AAC compared with patients with no AAC. Both moderate and severe AAC were associated with reduced improvement in LBP after surgery (moderate AAC: OR = 0.44, 95% CI: 0.22-0.85, P = 0.016; severe AAC: OR = 0.41, 95% CI: 0.2-0.82, P = 0.012). This study demonstrates an independent association between AAC and LBP and reduced improvement after surgery. Evaluation of AAC could play a role in patient education and might be considered part of the differential diagnosis for LBP, although further prospective studies are needed.

Abdominal aortic calcification is independently associated with increased atrophy and fatty infiltration of the lumbar paraspinal muscles: a retrospective cross-sectional study

BACKGROUND

Aortic abdominal calcification (AAC) is associated with spine-related conditions, such as lower back pain and reduced bone mineral density. Similar to peripheral vascular disease, AAC possibly reduces blood flow to the lumbar posterior paraspinal muscles (PPM) which may lead to atrophy and increased fatty infiltration.

METHODS

Imaging of patients with lower back pain was analyzed. AAC was assessed on lateral lumbar radiographs according to the Kauppila classification. The cross-sectional area of the PPM was measured on a T2-weighted axial MRI sequence and the functional cross-sectional area (fCSA) and fatty infiltration (FI) were calculated with custom software. The association of AAC and FI as well as AAC and fCSA was assessed by multivariable linear regression, adjusted for age, sex, body mass index (BMI), diabetes, and smoking.

RESULTS

Two hundred and thirty patients (47.8% female) with a median age of 60 years (IQR 48-68) were analyzed. In patients, without AAC the median FI of the PPM was 33.3% (IQR 29.1-37.6%), compared to 44.6% (IQR 38.5-54.3%) in patients with AAC (p < 0.001). In the multivariable linear regression, both fCSA and FI of the PPM were significantly and independently associated with the degree of AAC (p = 0.037 and p = 0.015, respectively).

CONCLUSIONS

This is the first study to demonstrate a significant and independent association between AAC and PPM morphology. The results of this study improve our understanding of the interaction between AAC and spinal musculature, with AAC being a reason for atrophy of the PPM.

Using T1 mapping indices to evaluate muscle function and predict conservative treatment outcomes in diabetic patients with peripheral arterial disease

OBJECTIVES

To investigate interstitial muscle fibrosis via T1 mapping indices and its relationships with muscle function and conservative treatment outcomes.

METHODS

A total of 49 DM patients with PAD were prospectively recruited from 2016 to 2017. All PAD patients underwent pre-treatment MRI with conservative treatment via a rehabilitation program and antiplatelet therapy. The need to require percutaneous transluminal angioplasty intervention was recorded as intolerance to conservative treatment outcomes. We quantified calf interstitial muscle fibrosis using T1 mapping indices (native T1, post-contrast T1, and the extracellular volume fraction [ECV]). Muscle function was evaluated using a 6-min walking test (6MWT) and a 3-min stepping test (3MST). PAD patients were divided into two groups according to their tolerance or intolerance of the conservative treatment. Pearson's correlation, reproducibility, and multivariable Cox hazard analyses were performed with p < 0.05 indicating statistical significance.

RESULTS

Among the T1 mapping indices in the posterior compartment of the calf in PAD patients, the native T1 value was significantly correlated with 6MWT (r =  -0.422, p = 0.010) and 3MST (r =  -0.427, p = 0.009). All T1 mapping indices showed excellent intra-observer and inter-observer correlations. ECV was an independent predictor of conservative treatment intolerance (average ECV, hazard ratio: 1.045, 95% confidence interval: 1.011-1.079, p = 0.009).

CONCLUSIONS

T1 mapping measurements are reproducible with excellent intra-observer and inter-observer correlations. T1 mapping indices may be predictive of treatment and functional outcomes and carry promise in patient evaluation.

TRIAL REGISTRATION

Clinical Trials Identifier: NCT02850432 .

KEY POINTS

• T1 mapping measurements of the calf muscles are reproducible with excellent intra-observer and inter-observer correlations (0.98 and 0.95 for anterior and posterior compartment muscle extracellular volume matrix [ECV] measurements, respectively). • ECV is shown to independently predict conservative treatment intolerance. • T1 mapping indices may be predictive of treatment and functional outcomes and carry promise in patient evaluation.

Effects of Six Weeks of Hypoxia Exposure on Hepatic Fatty Acid Metabolism in ApoE Knockout Mice Fed a High-Fat Diet

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease with a characteristic of abnormal lipid metabolism. In the present study, we employed apolipoprotein E knockout (ApoE KO) mice to investigate the effects of hypoxia exposure on hepatic fatty acid metabolism and to test whether a high-fat diet (HFD) would suppress the beneficial effect caused by hypoxia treatment. ApoE KO mice were fed a HFD for 12 weeks, and then were forwarded into a six-week experiment with four groups: HFD + normoxia, normal diet (ND) + normoxia, HFD + hypoxia exposure (HE), and ND + HE. The C57BL/6J wild type (WT) mice were fed a ND for 18 weeks as the baseline control. The hypoxia exposure was performed in daytime with normobaric hypoxia (11.2% oxygen, 1 h per time, three times per week). Body weight, food and energy intake, plasma lipid profiles, hepatic lipid contents, plasma alanine aminotransferase (ALT) and aspartate aminotransferase (AST), and molecular/biochemical makers and regulators of the fatty acid synthesis and oxidation in the liver were measured at the end of interventions. Six weeks of hypoxia exposure decreased plasma triglycerides (TG), total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-C) contents but did not change hepatic TG and non-esterified fatty acid (NEFA) levels in ApoE KO mice fed a HFD or ND. Furthermore, hypoxia exposure decreased the mRNA expression of Fasn, Scd1, and Srebp-1c significantly in the HFD + HE group compared with those in the HFD + normoxia group; after replacing a HFD with a ND, hypoxia treatment achieved more significant changes in the measured variables. In addition, the protein expression of HIF-1α was increased only in the ND + HE group but not in the HFD + HE group. Even though hypoxia exposure did not affect hepatic TG and NEFA levels, at the genetic level, the intervention had significant effects on hepatic metabolic indices of fatty acid synthesis, especially in the ND + HE group, while HFD suppressed the beneficial effect of hypoxia on hepatic lipid metabolism in male ApoE KO mice. The dietary intervention of shifting HFD to ND could be more effective in reducing hepatic lipid accumulation than hypoxia intervention.

NADPH oxidase family proteins: signaling dynamics to disease management

Reactive oxygen species (ROS) are pervasive signaling molecules in biological systems. In humans, a lack of ROS causes chronic and extreme bacterial infections, while uncontrolled release of these factors causes pathologies due to excessive inflammation. Professional phagocytes such as neutrophils (PMNs), eosinophils, monocytes, and macrophages use superoxide-generating NADPH oxidase (NOX) as part of their arsenal of antimicrobial mechanisms to produce high levels of ROS. NOX is a multisubunit enzyme complex composed of five essential subunits, two of which are localized in the membrane, while three are localized in the cytosol. In resting phagocytes, the oxidase complex is unassembled and inactive; however, it becomes activated after cytosolic components translocate to the membrane and are assembled into a functional oxidase. The NOX isoforms play a variety of roles in cellular differentiation, development, proliferation, apoptosis, cytoskeletal control, migration, and contraction. Recent studies have identified NOX as a major contributor to disease pathologies, resulting in a shift in focus on inhibiting the formation of potentially harmful free radicals. Therefore, a better understanding of the molecular mechanisms and the transduction pathways involved in NOX-mediated signaling is essential for the development of new therapeutic agents that minimize the hyperproduction of ROS. The current review provides a thorough overview of the various NOX enzymes and their roles in disease pathophysiology, highlights pharmacological strategies, and discusses the importance of computational modeling for future NOX-related studies.

Effect of nebivolol on altered skeletal and cardiac muscles induced by dyslipidemia in rats: impact on oxidative and inflammatory machineries

AIM

High cholesterol diet is greatly linked to deleterious health consequences. In this work we tried to explore direct effects of high cholesterol diet on striated (skeletal and cardiac) muscle tissues and the mechanisms by which nebivolol could improve such harmful effects.

METHODS

The study included 24 healthy adult male albino rats weighing 200-220 grams that were assigned into four groups: control group, control drug group, high cholesterol diet fed groups; one untreated the other was treated with nebivolol.

RESULTS

In the cholesterol fed group, we found decreased blood HDL and NO with elevated total cholesterol, triglycerides, myoglobin, CK, LDH, ALP, in addition to elevated muscle tissue levels of HIF-1, NF-kB, MDA, and decreased expression of both eNOS, reduced GSH. Wire hanging test time was shorter in the high cholesterol group than control group rats, which was confirmed histologically by increased striated muscle fibre thickness and cytochrome area %. Nebivolol treatment ameliorated the effects of high cholesterol diet.

CONCLUSION

High cholesterol diet caused myopathic changes in rat striated muscle tissues mostly due to oxidative stress associated with enhanced NF-kB and HIF-1 expression. Nebivolol appears beneficial in the management of hypercholesterolaemia-induced striated muscle injury.

Antioxidative and Angiogenic Hyaluronic Acid-Based Hydrogel for the Treatment of Peripheral Artery Disease

Peripheral arterial disease (PAD) is a progressive atherosclerotic disorder characterized by blockages of the arteries supplying the lower extremities. Ischemia initiates oxidative damage and mitochondrial dysfunction in the legs of PAD patients, causing injury to the tissues of the leg, significant decline in walking performance, leg pain while walking, and in the most severe cases, nonhealing ulcers and gangrene. Current clinical trials based on cells/stem cells, the trophic factor, or gene therapy systems have shown some promising results for the treatment of PAD. Biomaterial matrices have been explored in animal models of PAD to enhance these therapies. However, current biomaterial approaches have not fully met the essential requirements for minimally invasive intramuscular delivery to the leg. Ideally, a biomaterial should present properties to ameliorate oxidative stress/damage and failure of angiogenesis. Recently, we have created a thermosensitive hyaluronic acid (HA) hydrogel with antioxidant capacity and skeletal muscle-matching stiffness. Here, we further optimized HA hydrogels with the cell adhesion peptide RGD to facilitate the development of vascular-like structures in vitro. The optimized HA hydrogel reduced intracellular reactive oxygen species levels and preserved vascular-like structures against H₂O₂-induced damage in vitro. HA hydrogels also provided prolonged release of the vascular endothelial growth factor (VEGF). After injection into rat ischemic hindlimb muscles, this VEGF-releasing hydrogel reduced lipid oxidation, regulated oxidative-related genes, enhanced local blood flow in the muscle, and improved running capacity of the treated rats. Our HA hydrogel system holds great potential for the treatment of the ischemic legs of patients with PAD.

Cysteamine Decreases Low-Density Lipoprotein Oxidation, Causes Regression of Atherosclerosis, and Improves Liver and Muscle Function in Low-Density Lipoprotein Receptor-Deficient Mice

Background

We have shown previously that low‐density lipoprotein (LDL) can be oxidized in the lysosomes of macrophages, that this oxidation can be inhibited by cysteamine, an antioxidant that accumulates in lysosomes, and that this drug decreases atherosclerosis in LDL receptor–deficient mice fed a high‐fat diet. We have now performed a regression study with cysteamine, which is of more relevance to the treatment of human disease.

Methods and Results

LDL receptor–deficient mice were fed a high‐fat diet to induce atherosclerotic lesions. They were then reared on chow diet and drinking water containing cysteamine or plain drinking water. Aortic atherosclerosis was assessed, and samples of liver and skeletal muscle were analyzed. There was no regression of atherosclerosis in the control mice, but cysteamine caused regression of between 32% and 56% compared with the control group, depending on the site of the lesions. Cysteamine substantially increased markers of lesion stability, decreased ceroid, and greatly decreased oxidized phospholipids in the lesions. The liver lipid levels and expression of cluster of differentiation 68, acetyl–coenzyme A acetyltransferase 2, cytochromes P450 (CYP)27, and proinflammatory cytokines and chemokines were decreased by cysteamine. Skeletal muscle function and oxidative fibers were increased by cysteamine. There were no changes in the plasma total cholesterol, LDL cholesterol, high‐density lipoprotein cholesterol, or triacylglycerol concentrations attributable to cysteamine.

Conclusions

Inhibiting the lysosomal oxidation of LDL in atherosclerotic lesions by antioxidants targeted at lysosomes causes the regression of atherosclerosis and improves liver and muscle characteristics in mice and might be a promising novel therapy for atherosclerosis in patients.

High-Intensity Interval Training and Moderate-Intensity Continuous Training Attenuate Oxidative Damage and Promote Myokine Response in the Skeletal Muscle of ApoE KO Mice on High-Fat Diet

The purpose of this study was to investigate the effects of high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) on the skeletal muscle in Apolipoprotein E knockout (ApoE KO) and wild-type (WT) C57BL/6J mice. ApoE KO mice fed with a high-fat diet were randomly allocated into: Control group without exercise (ApoE^-/- CON), HIIT group (ApoE^-/- HIIT), and MICT group (ApoE^-/- MICT). Exercise endurance, blood lipid profile, muscle antioxidative capacity, and myokine production were measured after six weeks of interventions. ApoE^-/- CON mice exhibited hyperlipidemia and increased oxidative stress, compared to the WT mice. HIIT and MICT reduced blood lipid levels, ROS production, and protein carbonyl content in the skeletal muscle, while it enhanced the GSH generation and potently promoted mRNA expression of genes involved in the production of irisin and BAIBA. Moreover, ApoE^-/- HIIT mice had significantly lower plasma HDL-C content, mRNA expression of MyHC-IIx and Vegfa165 in EDL, and ROS level; but remarkably higher mRNA expression of Hadha in the skeletal muscle than those of ApoE^-/- MICT mice. These results demonstrated that both exercise programs were effective for the ApoE KO mice by attenuating the oxidative damage and promoting the myokines response and production. In particular, HIIT was more beneficial to reduce the ROS level in the skeletal muscle.

Effects from the induction of heat shock proteins in a murine model due to progression of aortic atherosclerosis

Heat shock proteins (HSPs) are molecular chaperones that repair denatured proteins. The relationship between HSPs and various diseases has been extensively studied. However, the relationship between HSPs and atherosclerosis remains unclear. In this study, we induced the expression of HSPs and analyzed the effects on the development/progression of atherosclerosis in vivo. Remarkably, when HSPs were induced in apolipoprotein E deficient (ApoE^-/-) mice prior to the formation of atheromas, the progression of atherosclerosis was inhibited; the short-term induction of HSPs significantly decreased the mRNA expression of intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) in the aorta. In contrast, the induction of HSPs after the formation of atheromas promoted the progression of atherosclerosis. In fact, the short-term induction of HSPs, after the formation of atheromas, significantly increased the mRNA expression of tumor necrosis factor-alpha, and interleukin 6 in the aorta. Of note, the induction of HSPs also promoted the formation of macrophage-derived foam cells. Overall, these results indicate that HSPs exerts different effects in the context of aortic atherosclerosis, depending on its degree of progression. Therefore, the induction and inhibition of HSPs should be considered for the prevention and treatment of atherosclerosis, respectively.

Platelet releasate normalises the compromised muscle regeneration in a mouse model of hyperlipidaemia

NEW FINDINGS

What is the central question of this study? What is the impact of obesity-independent hyperlipidaemia on skeletal muscle stem cell function of ApoE-deficient (ApoE^-/- ) mice? What is the main finding and its importance? Compromised muscle stem cell function accounts for the impaired muscle regeneration in hyperlipidaemic ApoE^-/- mice. Importantly, impaired muscle regeneration is normalised by administration of platelet releasate.

ABSTRACT

Muscle satellite cells are important stem cells for skeletal muscle regeneration and repair after injury. ApoE-deficient mice, an established mouse model of hyperlipidaemia and atherosclerosis, show evidence of oxidative stress-induced lesions and fat infiltration in skeletal muscle followed by impaired repair after injury. However, the mechanisms underpinning attenuated muscle regeneration remain to be fully defined. Key to addressing the latter is to understand the properties of muscle stem cells from ApoE-deficient mice and their myogenic potential. Muscle stem cells from ApoE-deficient mice were cultured both ex vivo (on single fibres) and in vitro (primary myoblasts) and their myogenic capacity was determined. Skeletal muscle regeneration was studied on days 5 and 10 after cardiotoxin injury. ApoE-deficient muscle stem cells showed delayed activation and differentiation on single muscle fibres ex vivo. Impaired proliferation and differentiation profiles were also evident on isolated primary muscle stem cells in culture. ApoE-deficient mice displayed impaired skeletal muscle regeneration after acute injury in vivo. Administration of platelet releasate in ApoE-deficient mice reversed the deficits of muscle regeneration after acute injury to wild-type levels. These findings indicate that muscle stem cell myogenic potential is perturbed in skeletal muscle of a mouse model of hyperlipidaemia. We propose that platelet releasate could be a therapeutic intervention for conditions with associated myopathy such as peripheral arterial disease.

Activating transcription factor 3 is a potential target and a new biomarker for the prognosis of atherosclerosis

ATF3 (activating transcription factor 3) is a member of the mammalian activation transcription factor/cAMP-responsive element-binding (CREB) family. It plays a role in inflammation and innate immunity, and suggests that ATF3 is associated with atherosclerosis. In our study, we analyzed datasets of atherosclerosis from the NCBI-GEO (Gene Expression Omnibus) database and found that expression levels of ATF3 were lower in macrophages from ruptured atherosclerotic plaques than from stable atherosclerotic plaques. Expression levels of ATF3 correlated with the stability of atherosclerotic plaques. KEGG analysis of different expression genes (DEGs) between ruptured and stable atherosclerotic plaques was performed by Metascape database. The PI3K-AKT pathway may be a potential pathway of the formation of ruptured atherosclerotic plaques. High-fat diet-induced atherosclerosis apoE-/- mice were divided into two groups: a model group and an ATF3 overexpression (OE)-group. Tests on atherosclerotic plaques in the aortic root suggested that absence of ATF3 and increase of macrophages may be risk factors for the formation of ruptured atherosclerotic plaques. We found decreased areas of lesions in aortic roots and branches of aortic arch, as well as increased lesional content of macrophages as well as TUNEL-positive areas. Consistent with these results, we found reduced degradation and incidence of elastic plate cracks accompanied by suppressed MMPs expression and transduction pathway protein PI3K/AKT activation. These data suggest that ATF3 is a signaling molecule that mediates the progression and stability of atherosclerotic plaques. ATF3 could be a potential new biomarker for the prognosis of atherosclerosis and may be a therapeutic target to reduce atherosclerosis.

Nutrition Management in Older Adults with Diabetes: A Review on the Importance of Shifting Prevention Strategies from Metabolic Syndrome to Frailty

The increasing prevalence of older adults with diabetes has become a major social burden. Diabetes, frailty, and cognitive dysfunction are closely related to the mechanisms of aging. Insulin resistance, arteriosclerosis, chronic inflammation, oxidative stress, and mitochondrial dysfunction may be common mechanisms shared by frailty and cognitive impairment. Hyperglycemia, hypoglycemia, obesity, vascular factors, physical inactivity, and malnutrition are important risk factors for cognitive impairment and frailty in older adults with diabetes. The impact of nutrients on health outcomes varies with age; thus, shifting diet therapy strategies from the treatment of obesity/metabolic syndrome to frailty prevention may be necessary in patients with diabetes who are over 75 years of age, have frailty or sarcopenia, and experience malnutrition. For the prevention of frailty, optimal energy intake, sufficient protein and vitamin intake, and healthy dietary patterns should be recommended. The treatment of diabetes after middle age should include the awareness of proper glycemic control aimed at extending healthy life expectancy with proper nutrition, exercise, and social connectivity. Nutritional therapy in combination with exercise, optimal glycemic and metabolic control, and social participation/support for frailty prevention can extend healthy life expectancy and maintain quality of life in older adults with diabetes mellitus.

Insights into the potential benefits of black soybean (Glycine max L.) polyphenols in lifestyle diseases

Black soybean (Glycine max L.), a cultivar containing abundant polyphenols in its seed coat such as anthocyanins and flavan-3-ols, has been reported to possess various health benefits toward lifestyle diseases. In this review article, the safety evaluation of polyphenol-rich black soybean seed coat extract (BE) and absorption of BE polyphenols are summarized. Additionally, we describe the antioxidant activity of BE polyphenols and their ability to induce antioxidant enzymes. The health benefits of BE and its polyphenols, such as anti-obesity and anti-hyperglycemic activities through the activation of AMP-activated protein kinase and translocation of glucose transporter 4, respectively, are also discussed. Furthermore, we found that black soybean polyphenols were involved in the improvement of vascular function. These emerging data require further investigation in scientific studies and human trials to evaluate the prevention of lifestyle diseases using black soybean polyphenols.

Peripheral arterial disease: the role of extracellular volume measurements in lower limb muscles with MRI

OBJECTIVES

Peripheral arterial disease (PAD) is characterised by arterial occlusion and fibrosis in the lower extremities. Extracellular volume matrix fraction (ECV) is a biomarker of skeletal muscle fibrosis, but has not been applied to the lower extremities with PAD. This study investigated the clinical feasibility of using ECV for calf muscle fibrosis quantification by comparing normal controls (NC) and PAD patients.

METHODS

From October 2016 to December 2017, we recruited patients with PAD, and patients with head and neck cancer receiving fibular flap as NC group. All participants underwent magnetic resonance imaging (MRI) to determine the ECV of the calves and the differences between the NC and PAD groups. ECV was calculated from T1 values at steady-state equilibrium, defined as the point in time after contrast agent injection when the variance of T1 relaxation time in blood and muscle becomes less than 5%.

RESULTS

A total of 46 patients (18 in the NC group and 28 in the PAD group) were recruited. Steady-state equilibrium was reached at 11-12 min after contrast agent injection. The NC group had significantly lower mean ECV than the PAD group (12.71% vs. 31.92%, respectively, p < 0.001). In the PAD group, the mean ECV was slightly lower in patients with collateral vessels than in those without (26.58% vs. 34.88%, respectively, p = 0.047).

CONCLUSION

Evaluation of skeletal fibrosis in PAD using ECV is feasible. ECV can help identify PAD patients with collateral vessel formation and lay the foundation for future research in PAD management.

KEY POINTS

• Steady-state equilibrium for ECV measurement of the lower limbs can be reached at around 11-12 min. • Quantification of lower limb muscle fibrosis by measuring ECV is clinically feasible and can be used to differentiate between patients with PAD and histologically proven normal controls. • ECV can differentiate PAD patients with or without visible collateral vessels, further expanding its role in identifying the presence of collateral supply in clinical decision-making.

Immunohistochemical biomarkers and distribution of telocytes in ApoE-/- mice

Telocytes had been identified as a peculiar stromal cell type implicated in tissue homeostasis and the development and pathophysiology of diseases. Telocyte existed in most organs and tissues in humans and animals. However, few studies have examined telocytes in ApoE gene deficient mice. In our studies, we verified the existence, the morphology and immunohistochemical characteristics of telocytes in critical organs of the ApoE^−/− mice. Male adult ApoE^−/− mice were selected as an experimental model. Immunohistochemical bio‐markers, such as CD34, CD117, CD28, Vimentin and PDGFR‐α were utilized to determine the distribution and morphology of telocytes in the heart, liver and kidney. Telocyte expressed positively for CD34 and CD117, and partial telocyte and telopode expressed positively for PDGFR‐α in heart and liver, but negatively in kidney. Double immunofluorescence assays for CD28/Vimentin, CD34/CD117 and CD34/PDGFR‐α were used to demonstrate the biochemistry speciality of telocytes, respectively. The evidence of telocytes in the ApoE^‐/‐ mice is the first step of our sturdy, which aims to demonstrate changes in telocytes in atherosclerosis in this animal model.

Attenuation of oxidative stress-induced lesions in skeletal muscle in a mouse model of obesity-independent hyperlipidaemia and atherosclerosis through the inhibition of Nox2 activity

Obesity leading to hyperlipidaemia and atherosclerosis is recognised to induce morphological and metabolic changes in many tissues. However, hyperlipidaemia can occur in the absence of obesity. The impact of the latter scenario on skeletal muscle and liver is not understood sufficiently. In this regard, we used the Apolipoprotein E-deficient (ApoE^-/-) mouse model, an established model of hyperlipidaemia and atherosclerosis, that does not become obese when subjected to a high-fat diet, to determine the impact of Western-type diet (WD) and ApoE deficiency on skeletal muscle morphological, metabolic and biochemical properties. To establish the potential of therapeutic targets, we further examined the impact of Nox2 pharmacological inhibition on skeletal muscle redox biology. We found ectopic lipid accumulation in skeletal muscle and the liver, and altered skeletal muscle morphology and intramuscular triacylglycerol fatty acid composition. WD and ApoE deficiency had a detrimental impact in muscle metabolome, followed by perturbed gene expression for fatty acid uptake and oxidation. Importantly, there was enhanced oxidative stress in the skeletal muscle and development of liver steatosis, inflammation and oxidative protein modifications. Pharmacological inhibition of Nox2 decreased reactive oxygen species production and protein oxidative modifications in the muscle of ApoE^-/- mice subjected to a Western-type diet. This study provides key evidence to better understand the pathophysiology of skeletal muscle in the context of hyperlipidaemia and atherosclerosis and identifies Nox2 as a potential target for attenuating oxidative stress in skeletal muscle in a mouse model of obesity-independent hyperlipidaemia.