Predictability of Cardiovascular Risk Scores for Carotid Atherosclerosis in Community-Dwelling Middle-Aged and Elderly Adults.

Background: The assessment of future risk of cardiovascular diseases (CVD) is strongly recommended for all asymptomatic adults without CVD history. Carotid atherosclerosis (CA) is a preclinical phenotype of CVDs. However, data on estimated future CVD risks with respect to preclinical atherosclerosis are limited. This community-based study aimed to assess the relationships between predicted CVD risks and CA. Methods: We enrolled 3908 subjects aged 40-74 years without CVD history and calculated their 10-year CVD risks using the Framingham Risk Score (FRS) and the Pooled Cohort Equations (PCE). Carotid plaque (CP) at the extracranial carotid arteries was determined by high-resolution B-mode ultrasonography and further classified into mild or advanced CA. Results: The means of FRS for CP-negative and mild and advanced CA were 9.0%, 14.4%, and 22.1%, respectively (p-value < 0.0001). The corresponding values for PCE score were 4.8%, 8.8%, and 15.0%, respectively (p-value < 0.0001). The odds ratios (ORs) of having CP per 5.0% increase in FRS and PCE score were 1.23 (95% CI, 1.19-1.28) and 1.36 (95% CI, 1.28-1.44), respectively. The corresponding values of having advanced CA were 1.24 (95% CI, 1.19-1.29) and 1.38 (95% CI, 1.30-1.48), respectively. Among the models of FRS or PCE plus other conventional CVD risk factors, the FRS + age model had the highest discrimination for the presence of CP (AUROC, 0.7533; 95% CI, 0.7375-0.7691) as well as for the presence of advanced CA (AUROC, 0.8034; 95% CI, 0.7835-0.8232). The calibration of the FRS + age models for the presences of CP and advanced CA was excellent (χ2 = 8.45 [p = 0.49] and 10.49 [p = 0.31], respectively). Conclusions: Estimated future CVD risks were significantly correlated with risks of having CA. Both FRS and PCE had good discrimination for the presences of CP and advanced CA.

Lactate induces C2C12 myoblasts differentiation by mediating ROS/p38 MAPK signalling pathway.

Lactate serves not merely as an energy substrate for skeletal muscle but also regulates myogenic differentiation, leading to an elevation of reactive oxygen species (ROS) levels. The present study was focused on exploring the effects of lactate and ROS/p38 MAPK in promoting C2C12 myoblasts differentiation. Our results demonstrated that lactate increased C2C12 myoblasts differentiation at a range of physiological concentrations, accompanied by enhanced ROS contents. We used n-acetylcysteine (NAC, a ROS scavenger) pretreatment and found that it delayed lactate-induced C2C12 myoblast differentiation by upregulating Myf5 expression on days 5 and 7 and lowering MyoD and MyoG expression. The finding implies that lactate accompanies ROS-dependent manner to promote C2C12 myoblast differentiation. Additionally, lactate significantly increased p38 MAPK phosphorylation to promote C2C12 cell differentiation, but pretreatment with SB203580 (p38 MAPK inhibitor) reduced lactate-induced C2C12 myoblasts differentiation. whereas lactate pretreatment with NAC inhibited p38 MAPK phosphorylation in C2C12 cells, demonstrating that lactate mediated ROS and regulated the p38 MAPK signalling pathway to promote C2C12 cell differentiation. In conclusion, our results suggest that the promotion of C2C12 myoblasts differentiation by lactate is dependent on ROS and the p38 MAPK signalling pathway. These observations reveal a beneficial role for lactate in increasing myogenesis through ROS-sensitive mechanisms as well as providing new ideas regarding the positive impact of ROS in improving the function of skeletal muscle.

Lactate ameliorates palmitate-induced impairment of differentiative capacity in C2C12 cells through the activation of voltage-gated calcium channels.

Palmitic acid (PA), a saturated fatty acid enriched in high-fat diet, has been implicated in the development of skeletal muscle regeneration dysfunction. This study aimed to examine the effects and mechanisms of lactate (Lac) treatment on PA-induced impairment of C2C12 cell differentiation capacity. Furthermore, the involvement of voltage-gated calcium channels in this context was examined. In this study, Lac could improve the PA-induced impairment of differentiative capacity in C2C12 cells by affecting Myf5, MyoD and MyoG. In addition, Lac increases the inward flow of Ca2+, and promotes the depolarization of the cell membrane potential, thereby activating voltage-gated calcium channels during C2C12 cell differentiation. The enchancement of Lac on myoblast differentiative capacity was abolished after the addition of efonidipine (voltage-gated calcium channel inhibitors). Therefore, voltage-gated calcium channels play an important role in improving PA-induced skeletal muscle regeneration disorders by exercising blood Lac. Our study showed that Lac could rescue the PA-induced impairment of differentiative capacity in C2C12 cells by affecting Myf5, MyoD and MyoG through the activation of voltage-gated calcium channels.

Advances in the Application of Transition-Metal Composite Nanozymes in the Field of Biomedicine.

Due to the limitation that natural peroxidase enzymes can only function in relatively mild environments, nanozymes have expanded the application of enzymology in the biological field by dint of their ability to maintain catalytic oxidative activity in relatively harsh environments. At the same time, the development of new and highly efficient composite nanozymes has been a challenge due to the limitations of monometallic particles in applications and the inherently poor enzyme-mimetic activity of composite nanozymes. The inherent enzyme-mimicking activity is due to Au, Ag, and Pt, along with other transition metals. Moreover, the nanomaterials exhibit excellent enzyme-mimicking activity when composited with other materials. Therefore, this paper focuses on composite nanozymes with simulated peroxidase activity that have been prepared using noble metals such as Au, Ag, and Pt and other transition metal nanoparticles in recent years. Their simulated enzymatic activity is utilized for biomedical applications such as glucose detection, cancer cell detection and tumor treatment, and antibacterial applications.

Advances in the application of metal oxide nanozymes in tumor detection and treatment.

Natural enzymes play an important role to support the regular life activities of the human body. However, the application conditions of natural enzymes are harsh and there are limitations in their use. As artificial enzymes, nanozymes possess the substrate specificity of natural enzymes. Due to the advantages of low cost, good stability and strong catalytic properties, nanozymes hold a wide range of applications in the fields of sensing, chemical, food and medicine. Some of the more common ones are noble metal nanozymes, metal oxide nanozymes and carbon-based nanozymes. Among them, metal oxide nanozymes have attracted much attention because of their decent fixity, exceedingly good physicochemical properties and other advantages. Today, malignant tumors pose a great danger to the human body and are a serious threat to human health. However, traditional treatments have more side effects, and finding new treatment modalities is particularly important for tumor treatment. For example, enzyme therapy can be used to catalyze reactions in the body to achieve tumor treatment. Nanozymes can exert enzymatic activity and effectively treat malignant tumors through catalysis and synergy, and have made certain progress. This paper reviews the detection and application of metal oxide nanozymes in tumor detection and treatment in recent years and provides an outlook on their future application and development.

Expression and electrophysiological characteristics of VGSC during mouse myoblasts differentiation.

Voltage-gated sodium channels (VGSC) are essential for triggering and relaying action potentials (AP), which perform critical functions in a variety of physiological processes, such as controlling muscle contractions and facilitating the release of neurotransmitters. In this study, we used a mouse C2C12 cell differentiation model to study the molecular expression and channel dynamics of VGSC and to investigate the exact role of VGSC in the development of muscle regeneration. Immunofluorescence, Real-time quantitative polymerase chain reaction, Western blot, and whole-cell patch clamp were employed for this purpose in mouse myoblasts. The findings revealed an increase in intracellular sodium concentration, NaV1.4 gene expression, and protein expression with the progress of differentiation (days 0, 1, 3, 5 and 7). Furthermore, VGSC dynamics exhibit the following characteristics: ① The increase of sodium current (INa); ② The decrease in the activation threshold and the voltage trigger maximum of INa; ③ A positive shift in the steady-state inactivation curve; ④ The recovery of INa during repolarization is delayed, the activity-dependent decay rate of INa was accelerated, and the proportionate amount of the fraction of activated channels was reduced. Based on these results, it is postulated that the activation threshold of AP could be decreased, and the refractory period could be extended with the extension of differentiation duration, which may contribute to muscle contraction. Taken together, VGSC provides a theoretical and empirical basis for exploring potential targets for neuromuscular diseases and other therapeutic muscle regeneration dysfunctions.

Cordycepin inhibits myogenesis via activating the ERK1/2 MAPK signalling pathway in C2C12 cells.

Cordycepin (with a molecular formula of C10H13N5O3), a natural adenosine isolated from Cordyceps militaris, has an important regulatory effect on skeletal muscle remodelling and quality maintenance. The aim of this study was to investigate the effect of cordycepin on myoblast differentiation and explore the underlying molecular mechanisms of this effect. Our results showed that cordycepin inhibited myogenesis by downregulating myogenic differentiation (MyoD) and myogenin (MyoG), preserved undifferentiated reserve cell pools by upregulating myogenic factor 5 (Myf5) and retinoblastoma-like protein p130 (p130), and enhanced energy reserves by decreasing intracellular reactive oxygen species (ROS) and enhancing mitochondrial membrane potential, mitochondrial mass, and ATP content. The effect of cordycepin on myogenesis was associated with increased phosphorylation of extracellular signal-regulated kinase 1/2 (p-ERK1/2). PD98059 (a specific inhibitor of p-ERK1/2) attenuated the inhibitory effect of cordycepin on C2C12 differentiation. The present study reveals that cordycepin inhibits myogenesis through ERK1/2 MAPK signalling activation accompanied by an increase in skeletal muscle energy reserves and improving skeletal muscle oxidative stress, which may have implications for its further application for the prevention and treatment of degenerative muscle diseases caused by the depletion of depleted muscle stem cells.

Associations of genetic markers of diabetes mellitus with carotid atherosclerosis: a community-based case-control study.

BACKGROUND: Diabetes mellitus (DM) is a well-established determinant of atherosclerosis and cardiovascular diseases (CVD). Recently, genome-wide association studies (GWAS) identified several single nucleotide polymorphism (SNP) significantly correlated with DM. The study aimed to explore the relationships of the top significant DM SNPs with carotid atherosclerosis (CA). METHODS: We used a case-control design and randomly selected 309 cases and 439 controls with and without, respectively, carotid plaque (CP) from a community-based cohort. Eight recent GWAS on DM in East Asians reported hundreds of SNPs with genome-wide significance. The study used the top significant DM SNPs, with a p-value < 10-16, as the candidate genetic markers of CA. The independent effects of these DM SNPs on CA were assessed by multivariable logistic regression analyses to control the effects of conventional cardio-metabolic risk factors. RESULTS: Multivariable analyses showed that, 9 SNPs, including rs4712524, rs1150777, rs10842993, rs2858980, rs9583907, rs1077476, rs7180016, rs4383154, and rs9937354, showed promising associations with the presence of carotid plaque (CP). Among them, rs9937354, rs10842993, rs7180016, and rs4383154 showed significantly independent effects. The means (SD) of the 9-locus genetic risk score (9-GRS) of CP-positive and -negative subjects were 9.19 (1.53) and 8.62 (1.63), respectively (p < 0.001). The corresponding values of 4-locus GRS (4-GRS) were 4.02 (0.81) and. 3.78 (0.92), respectively (p < 0.001). The multivariable-adjusted odds ratio of having CP for per 1.0 increase in 9-GRS and 4-GRS were 1.30 (95% CI 1.18-1.44; p = 4.7 × 10-7) and 1.47 (95% CI 1.74-9.40; p = 6.1 × 10-5), respectively. The means of multi-locus GRSs of DM patients were similar to those of CP-positive subjects and higher than those of CP-negative or DM-negative subjects. CONCLUSIONS: We identified 9 DM SNPs showing promising associations with CP. The multi-locus GRSs may be used as biomarkers for the identification and prediction of high-risks subjects for atherosclerosis and atherosclerotic diseases. Future studies on these specific SNPs and their associated genes may provide valuable information for the preventions of DM and atherosclerosis.

Combined effects of hypertension, hyperlipidemia, and diabetes mellitus on the presence and severity of carotid atherosclerosis in community-dwelling elders: A community-based study.

BACKGROUND: Hypertension, hyperlipidemia, and diabetes mellitus (DM) are common cardiovascular disease (CVD) comorbidities and well-known major determinants of atherosclerosis. However, their combined effects and relative contributions have not been well explored. This study aimed to characterize the characteristics of carotid atherosclerosis and dissect the relative effects of these common CVD comorbidities on the presence and severity of carotid atherosclerosis in community-dwelling elderly individuals. METHODS: We enrolled 817 elders from communities in northern Taiwan. We evaluated their cardiovascular risk profiles and scanned their extracranial carotid arteries using high-resolution ultrasonography systems. RESULTS: The prevalence rates for hypertension, hyperlipidemia, and DM were 45.4%, 37.1%, and 16.8%, respectively. Sixty-two (7.6%) and 188 (23.0%) elderly had all three and two of these common CVD comorbidities, respectively. The prevalent rates of carotid plaque and moderate-to-severe atherosclerosis were 62.9% and 35.5%, respectively. The percentages of one or more common CVD comorbidities in elders with carotid plaque and moderate-to-severe atherosclerosis were 78.2% and 83.1%, respectively. Multivariate analyses showed that the number of common CVD comorbidities was the most predictive determinant. Multivariable-adjusted odds ratios (ORs) per comorbidity for the presence of carotid plaque and advanced carotid atherosclerosis were 1.52 (95% CI, 1.28-1.81) and 1.57 (95% CI, 1.28-1.93), respectively. Models containing hypertension and DM were the second most predictive. Combinatory analyses showed distinct relationship patterns between carotid atherosclerosis and hypertension, hyperlipidemia, and DM. Hypertension was significantly correlated with higher ORs for the presence of carotid plaque and advanced carotid atherosclerosis but not for hyperlipidemia. CONCLUSION: Carotid plaques are highly prevalent in community-dwelling elders. The number of common CVD comorbidities was the most predictive determinant of carotid plaques and advanced carotid atherosclerosis. Our results indicate that to reduce the impact of atherosclerotic diseases, blood pressure controls precede the control of blood lipids and glucose in the community-dwelling elders.

Cordycepin suppresses glutamatergic and GABAergic synaptic transmission through activation of A1 adenosine receptor in rat hippocampal CA1 pyramidal neurons.

Cordycepin (known as 3-deoxyadenosine, CRD), a natural product from the valuable traditional Chinese medicine Cordyceps militaris, has been reported to improve cognitive function and modulate neuroprotective effects on the central nervous system (CNS). However, the modulating mechanisms of cordycepin on information processing in hippocampal CA1 pyramidal neurons are not fully understood. To clarify how cordycepin modulates synaptic responses of pyramidal neurons in rat hippocampal CA1 region, we conducted an electrophysiological experiment using whole-cell patch-clamp technique. The spontaneous and miniature excitatory postsynaptic currents (sEPSCs and mEPSCs, respectively) and the spontaneous and miniature inhibitory postsynaptic currents (sIPSCs and mIPSCs, respectively) recorded by this technique evaluated pure single or multi-synapse responses and enabled us to accurately quantify how cordycepin influenced the pre and postsynaptic aspects of synaptic transmission. The present results showed that cordycepin significantly decreased the frequency of both glutamatergic and GABAergic postsynaptic currents without affecting the amplitude, while these inhibitory effects were antagonized by the A1 adenosine receptor antagonist (DPCPX), but not the A2A (ZM 241385), A2B (MRS1754) and A3 (MRS1191) adenosine receptor antagonists. Taken together, our results suggested that cordycepin had a clear presynaptic effect on glutamatergic and GABAergic transmission, and provided novel evidence that cordycepin suppresses the synaptic transmission through the activation of A1AR.

Prevalences of diabetes mellitus and carotid atherosclerosis and their relationships in middle-aged adults and elders: a community-based study.

BACKGROUND/PURPOSE: Atherosclerosis and diabetes mellitus (DM) are both severe chronic diseases that cause huge burdens on patients' families and societies. Connections between the two diseases have brought high attention recently, however, population-based study with large sample size was few. The study aimed to explore the relationship between carotid atherosclerosis and DM. METHODS: We enrolled 3908 adults aged 40-74 years from communities and measured their cardio-metabolic profiles and scanned their carotid arteries bilaterally. RESULTS: The overall prevalence rates of carotid plaque and DM were 34.4 and 10.7%, respectively. The age-specific prevalence rates of DM and carotid plaque were nearly linearly correlated in both sexes (both Pearson's correlation coefficient r > 0.97). The prevalence rates of carotid plaque, total plaque number ≥3, maximum diameter stenosis ≥30%, and plaque score ≥3 were 53.6, 24.8, 19.1, and 28.6%, respectively, in DM patients and were 32.1, 9.4, 9.8, and 11.2%, respectively, in non-DM controls. After adjustment for other conventional risk factors, the multivariable-adjusted OR of having carotid plaque was 1.60 (95% CI 1.27-2.01) and were 2.06 (95% CI 1.55-2.75), 1.33 (95% CI 0.99-1.78), and 2.03 (95% CI 1.55-2.65) for total plaque number ≥3, maximum diameter stenosis ≥30%, and plaque score ≥3, respectively. CONCLUSION: We demonstrated that prevalences of DM were linearly correlated with prevalences of carotid plaque and DM patients had higher prevalence rates of carotid plaque and more advanced carotid atherosclerosis than non-DM controls. Our results indicated the need to address the role of DM in atherosclerosis development.

TLR4-mediated induction of TLR2 signaling is critical in the pathogenesis and resolution of otitis media.

Otitis media is the most prevalent childhood disease in developed countries. The involvement of Toll-like receptors (TLRs) in otitis media pathophysiology has been implicated by studies in cell lines and association studies of TLR gene polymorphisms. However, precise functions of TLRs in the etiology of otitis media in vivo have not been examined. We investigated the inflammatory response to nontypeable Haemophilus influenzae using a model of otitis media in wild-type, TLR2(- /-) and TLR4(-/ -) mice by gene microarray, qPCR, immunohistochemistry, Western blot analysis and histopathology. Toll-like receptor-2(- /-) and TLR4(- /-) mice exhibited a more profound, persistent inflammation with impaired bacterial clearance compared to controls. While wild-type mice induced tumor necrosis factor-a (TNF) after non-typeable H. influenzae challenge, TLR2(-/-) and TLR4(-/-) mice lack TNF induction in the early phase of otitis media. Moreover, lack of TLR2 resulted in a late increase in IL-10 expression and prolonged failure to clear bacteria. Toll-like receptor-4(-/- ) mice showed impaired early bacterial clearance and loss of TLR2 induction in early otitis media. Our results demonstrate that both TLR2 and TLR4 signalling are critical to the regulation of infection in non-typeable H. influenzae-induced otitis media. Toll-like receptor-4 signalling appears to induce TLR2 expression, and TLR2 activation is critical for bacterial clearance and timely resolution of otitis media.