Relevance of the antioxidant properties of methotrexate and doxycycline to their treatment of cardiovascular disease

Oroxylin A reverses SHP-2 oxidative inactivation in GPVI signaling to suppress platelet activation and thrombus formation

BACKGROUND

Arterial thrombotic events are the leading causes of death worldwide, and the therapeutic effects of current antiplatelet drugs are not fully satisfactory. Oroxylin A (OroA), a flavone compound extracted from Scutellaria radix, possesses cardioprotective and many other pharmacological effects. While platelets play a crucial role in the development of myocardial infarction, the direct effects of OroA on platelet activation and thrombosis have yet to be investigated.

METHODS

FeCl₃-induced arteriole thrombosis and whole-blood perfusion were used to assess the inhibitory effect of OroA on thrombus formation. A myocardial ischemia model was employed to evaluate the protective effect of OroA on myocardial injury. Multiple platelet function studies including platelet aggregation, platelet spreading, clot retraction were performed. Network pharmacology, flow cytometry, enzyme-linked immunosorbent assay, co-immunoprecipitation and western blot were utilized to explore the mechanism of OroA on platelet activation.

RESULTS

OroA inhibited thrombus formation with less bleeding risk compared with aspirin. OroA protected against myocardial injury by suppressing microvascular thrombosis and platelet infiltration. OroA suppressed different agonist-induced platelet activation in a concentration-dependent manner, showing greater antiplatelet activity against collagen-induced platelet aggregation compared to ADP or thrombin-induced aggregation. OroA decreased granule release, integrin αIIbβ3 activation, platelet spreading and clot retraction. As a flavone, OroA boosted superoxide dismutase (SOD) and glutathione (GSH) activities and decreased malondialdehyde (MDA), oxidized glutathione (GSSG) and ROS levels in platelets during oxidative stress. OroA binds to SHP-2 and prevents its oxidative inactivation, leading to the tyrosine dephosphorylation of Src, Syk and PLCγ2, as well as the reduction of Ca2+ influx and PKC phosphorylation in GPVI signaling.

CONCLUSIONS

OroA inhibits platelet activation, thrombus formation and myocardial injury via reversing SHP-2 oxidative inactivation thereby attenuating collagen-induced GPVI signaling. With minor bleeding risk and no obvious pharmacological toxicity, OroA holds promising therapeutic potential as an antithrombotic drug.

Association between composite dietary antioxidant index and stroke among individuals with diabetes

BACKGROUND

Recent research has underscored the potentially protective role of dietary antioxidants against chronic conditions, such as cardiovascular diseases and stroke. The composite dietary antioxidant index (CDAI), which reflects the overall intake of key dietary antioxidants, has been identified as a crucial metric for exploring this relationship. Although previous research has shown a negative correlation between CDAI levels and stroke risk in prediabetic individuals, there remains a substantial gap in understanding this association among individuals with dia-betes, who are at an inherently greater risk for cerebrovascular events.

AIM

To investigate the association between CDAI and stroke risk in individuals with diabetes.

METHODS

Using a cross-sectional study design, this investigation analyzed data from the National Health and Nutrition Examination Survey spanning from 2003 to 2018 that included 6735 participants aged over 20 years with diabetes. The CDAI was calculated from 24-h dietary recalls to assess intake of key antioxidants: Vitamins A, C, and E; carotenoids; selenium; and zinc. Multivariate logistic regression and restricted cubic spline analysis were used to rigorously examine the relationship between CDAI and stroke risk.

RESULTS

The participant cohort, with an average age of 59.5 years and a slight male majority, reflected the broader demographic characteristics of individuals with diabetes. The analysis revealed a strong inverse relationship between CDAI levels and stroke risk. Remarkably, those in the highest quintile of CDAI demonstrated a 43% lower prevalence of stroke compared to those in the lowest quintile, even after adjustments for various confounders. This finding not only highlights the negative association between CDAI and stroke risk but also underscores the significant potential of antioxidant-rich diets in reducing stroke prevalence among patients with diabetes.

CONCLUSION

Our findings suggested that CDAI was inversely associated with stroke prevalence among patients with diabetes. These results suggest incorporating antioxidant-rich foods into dietary regimens as a potential strategy for stroke prevention.

Doxycycline inhibits neurotropic enterovirus proliferation in vitro

Human enteroviruses (EVs) represent a global public health concern due to their association with a range of serious pediatric illnesses. Despite the high morbidity and mortality exerted by EVs, no broad-spectrum antivirals are currently available. Herein, we presented evidence that doxycycline can inhibit in vitro replication of various neurotropic EVs, including enterovirus A71 (EV-A71), enterovirus D68 (EV-D68), and coxsackievirus (CV)-A6, in a dose-dependent manner. Further investigations indicated that the drug primarily acted at the post-entry stage of virus infection in vitro, with inhibitory effects reaching up to 89 % for EV-A71 when administered two hours post-infection. These findings provide valuable insights for the development of antiviral drugs against EV infections.

Doxycycline reduces liver and kidney injuries in a rat hemorrhagic shock model

BACKGROUND

Hemorrhagic shock (HS), which causes insufficient tissue perfusion, can result in multiple organ failure (MOF) and death. This study aimed to evaluate whether doxycycline (DOX) protects cardiovascular, kidney, and liver tissue from damage in a rat model of HS. Immediately before the resuscitation, DOX (10 mg/kg; i.v.) was administered, and its protective effects were assessed 24 h later. Mean arterial pressure, renal blood flow, heart rate, vasoactive drug response, and blood markers such as urea, creatinine, AST, ALT, CPK, CPR, and NOx levels were determined.

RESULTS

We showed that DOX has a significant effect on renal blood flow and on urea, creatinine, AST, ALT, CPK, and NOx. Morphologically, DOX reduced the inflammatory process in the liver tissue.

CONCLUSIONS

We conclude that DOX protects the liver and kidney against injury and dysfunction in a HS model and could be a strategy to reduce organ damage associated with ischemia-and-reperfusion injury.

Association between composite dietary antioxidant index and coronary heart disease among US adults: a cross-sectional analysis

BACKGROUND

The Composite Dietary Antioxidant Index (CDAI) is a dietary antioxidant score that plays a protective role in many diseases, including depression, osteoporosis, papillomavirus infection, etc. However, the association between CDAI and coronary heart disease (CHD) is currently unclear. We aim to explore the correlations between CDAI and the risk of CHD.

METHODS

Eligible participants were obtained from the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2018. All participants in this cross-sectional study are required to undergo two separate 24-h dietary recall interviews. Average daily intakes of dietary antioxidants were used to calculate CDAI. CHD status was determined through a questionnaire. Weighted multiple logistic regression models were used to evaluate the relationship between CDAI and CHD. Moreover, we also used restricted cubic spline to explore Non-linear correlations. Sensitivity analysis using unweighted logistic analysis and subgroup analysis were used to demonstrate the stability of the results.

RESULTS

A total of 34,699 participants were eligible for analysis.Compared to the participants without CHD, the participants with CHD showed lower levels of CDAI. After adjusting confounding factors in the multivariate weighted logistic regression model, CDAI was inversely associated with CHD (Q4 vs. Q1, OR = 0.65 (0.51-0.82, P < 0.001). Restricted cubic spline showed that there was a negative non-linear correlation (L-shaped) between CDAI and CHD, suggesting a potential saturation effect at higher CDAI levels, with the inflection point of 0.16. Sensitivity analysis showed that the results were stable. No significant statistically interaction was showed in subgroup analysis.

CONCLUSIONS

There was a negative non-linear correlation between CDAI and CHD in US adults. However, further prospective studies are still needed to reveal their relationship.

Difference in immune responses to Candida albicans in two inbred strains of male rats

OBJECTIVE

To investigate the influence of strain differences in immune response on the pathogenesis of oral candidiasis in Dark Agouti (DA) and Albino Oxford (AO) inbred strains of rats.

DESIGN

Seventy male 8-weeks old DA and AO rats were inoculated with Candida albicans to induce three different experimental models of oral candidiasis, one immunocompetent and two immunocompromised models. The animals were sacrificed after 16 days from the beginning of the experiment followed by collecting the samples of the tongue dorsum and blood for histopathological (PAS and H&E staining), immunohistochemical, qRT-PCR, and oxidative stress analyses.

RESULTS

Histopathological and immunohistochemical analyses revealed lower levels of epithelial colonization, epithelial damage, and inflammatory infiltration in DA compared to AO strain of rats. DA rats had fewer CD45, CD68, and CD3 positive cells but more HIS 48 positive cells than AO rats. The expressions of IL-1β, TNFα, IFN-γ, IL-10 and TGF-β1 were consistently higher in DA strain across all experimental models. However, the expressions of IL-4 and IL-17 differed inconsistently between DA and AO strain in various experimental models. Strain differences were observed in levels of prooxidative hydrogen peroxide and lipid peroxidation, with higher levels presented in AO rats compared to DA rats, while antioxidative parameters presented little yet inconsistent difference between strains.

CONCLUSION

DA strain of rats consistently presented lower susceptibility to oral infection with C. albicans compared to AO strain with robust Th1/Th17 immune response indicating the importance of the genetic background on the development of oral candidiasis.

Ammonia-induced oxidative stress triggered proinflammatory response and apoptosis in pig lungs

Ammonia, a common toxic gas, is not only one of the main causes of haze, but also can enter respiratory tract and directly affect the health of humans and animals. Pig was used as an animal model for exploring the molecular mechanism and dose effect of ammonia toxicity to lung. In this study, the apoptosis of type II alveolar epithelial cells was observed in high ammonia exposure group using transmission electron microscopy. Gene and protein expression analysis using transcriptome sequencing and western blot showed that low ammonia exposure induced T-cell-involved proinflammatory response, but high ammonia exposure repressed the expression of DNA repair-related genes and affected ion transport. Moreover, high ammonia exposure significantly increased 8-hydroxy-2-deoxyguanosine (8-OHdG) level, meaning DNA oxidative damage occurred. In addition, both low and high ammonia exposure caused oxidative stress in pig lungs. Integrated analysis of transcriptome and metabolome revealed that the up-regulation of LDHB and ND2 took part in high ammonia exposure-affected pyruvate metabolism and oxidative phosphorylation progress, respectively. Inclusion, oxidative stress mediated ammonia-induced proinflammatory response and apoptosis of porcine lungs. These findings may provide new insights for understanding the ammonia toxicity to workers in livestock farms and chemical fertilizer plants.

Doxycycline Attenuates Doxorubicin-Induced Cardiotoxicity by Improving Myocardial Energy Metabolism in Rats

Aim: Evaluate the influence of doxycycline, an anti-inflammatory and matrix metalloproteinase (MMP) inhibitor, on the attenuation of chronic doxorubicin-induced cardiotoxicity in rats. Methods: We allocated male Wistar rats into four groups: control (C), doxorubicin (D), doxycycline (inhibitor of MMP, IM), and Dox + doxycycline (DIM). Groups IM and DIM received doxycycline (5 mg/kg, IP) once a week for 4 weeks. In addition, 48 h after every doxycycline injection, groups D and DIM received Dox (5 mg/kg, IP). We performed echocardiogram and evaluated TIMP-4 and collagen I protein expression, MMP-2 activity, and oxidative stress and myocardial metabolism. Results: Doxorubicin promotes left atrium (LA) and left ventricle (LV) dilatation and decreases in LV fractional shortening, which was improved by doxycycline. Moreover, doxycycline attenuated the LV cardiomyocyte hypertrophy and collagen type I expression. Doxorubicin increased phosphofructokinase and decreased beta-hydroxyacyl Co-A dehydrogenase, pyruvate dehydrogenase, citrate synthase, and ATP synthase activity, which was partially attenuated by doxycycline. Lastly, doxycycline improved antioxidant enzyme activity in the DIM group. Conclusion: Doxorubicin increases oxidative stress and promotes changes in myocardial energy metabolism, accompanied by structural and functional changes. Doxycycline attenuated the doxorubicin-induced cardiotoxicity, at least in part, through changes in myocardial energy metabolism.

Malondialdehyde-Acetaldehyde Modified (MAA) Proteins Differentially Effect the Inflammatory Response in Macrophage, Endothelial Cells and Animal Models of Cardiovascular Disease

Chronic inflammation plays a critical role in the pathogenesis of atherosclerosis. Currently, the mechanism(s) by which inflammation contributes to this disease are not entirely understood. Inflammation is known to induce oxidative stress, which can lead to lipid peroxidation. Lipid peroxidation can result in the production of reactive by-products that can oxidatively modify macromolecules including DNA, proteins, and lipoproteins. A major reactive by-product of lipid peroxidation is malondialdehyde (MDA). MDA can subsequently break down to form acetaldehyde (AA). These two aldehydes can covalently interact with the epsilon (ε)-amino group of lysines within proteins and lipoproteins leading to the formation of extremely stable, highly immunogenic malondialdehyde/acetaldehyde adducts (MAA-adducts). The aim of this study was to investigate the inflammatory response to MAA-modified human serum albumin (HSA-MAA) and low-density lipoprotein (LDL-MAA). We found that animals injected with LDL-MAA generate antibodies specific to MAA-adducts. The level of anti-MAA antibodies were further increased in an animal model of atherosclerosis fed a Western diet. An animal model that combined both high fat diet and immunization of MAA-modified protein resulted in a dramatic increase in antibodies to MAA-adducts and vascular fat accumulation compared with controls. In vitro exposure of endothelial cells and macrophages to MAA-modified proteins resulted in increased fat accumulation as well as increased expression of adhesion molecules and pro-inflammatory cytokines. The expression of cytokines varied between the different cell lines and was unique to the individual modified proteins. The results of these studies demonstrate that different MAA-modified proteins elicit unique responses in different cell types. Additionally, the presence of MAA-modified proteins appears to modulate cellular metabolism leading to increased accumulation of triglycerides and further progression of the inflammatory response.

Association of Rosacea With Cardiovascular Disease: A Retrospective Cohort Study

Background There is emerging evidence that rosacea, a chronic cutaneous inflammatory disease, is associated with various systemic diseases. However, its association with cardiovascular disease (CVD) remains controversial. We aimed to investigate whether patients with rosacea are at increased risk of developing CVD. Methods and Results This retrospective cohort study from the Korean National Health Insurance Service-Health Screening Cohort included patients with newly diagnosed rosacea (n=2681) and age-, sex-, and index year-matched reference populations without rosacea (n=26 810) between 2003 and 2014. The primary outcome was subsequent CVD including coronary heart disease and stroke. Multivariable Cox regression analyses were used to evaluate adjusted hazard ratios for subsequent CVD adjusted for major risk factors of CVD. Compared with the reference population (13 410 women; mean [SD] age, 57.7 [9.2] years), patients with rosacea (1341 women; mean [SD] age, 57.7 [9.2] years) displayed an increased risk for CVD (adjusted hazard ratios, 1.20; 95% CI, 1.03-1.40) and coronary heart disease (adjusted hazard ratios, 1.29; 95% CI, 1.05-1.60). The risk for stroke was not significantly elevated (adjusted hazard ratios, 1.12; 95% CI, 0.91-1.37). Conclusions This study suggests that patients with rosacea are more likely to develop subsequent CVD. Proper education for patients with rosacea to manage other modifiable risk factors of CVD along with rosacea is needed.

Methotrexate and cardiovascular risk in rheumatic diseases:A comprehensive review

Introduction: Management of inflammatory rheumatic diseases has evolved based on improved treatment strategies and better management of comorbidities, specifically cardiovascular risk. Methotrexate is one of the first-line treatments in the management of inflammatory rheumatic diseases, but its cardiovascular effects are poorly understood. The purpose of this review is to assess the cardiovascular impact of methotrexate in inflammatory rheumatic disease.Areas covered: Current knowledge about the mechanism of action of methotrexate on cardiovascular tissue is presented. A review of the literature in the Medline, Cochrane and Embase databases was performed. Current data about the cardiovascular effects of methotrexate in rheumatoid arthritis, psoriatic arthritis, and psoriasis are presented.Expert opinion: Mechanism of action of methotrexate is based on the antagonism of purines. It reduces systemic inflammation and oxidative stress and improves the major cardiovascular risk factors. Methotrexate improves cardiovascular risk in rheumatoid arthritis, psoriasis and psoriatic arthritis, but the mechanisms involved are partially identified. Data are controversial regarding its effects on endothelial function and atherosclerosis. Conversely, in the general population and in patients with HIV infection, methotrexate does not modify cardiovascular outcomes. Thus, methotrexate only improves cardiovascular risk by reducing systemic inflammation, and should not be used to prevent cardiovascular events.

In vivo guiding inorganic nanozymes for biosensing and therapeutic potential in cancer, inflammation and microbial infections

Researchers have recently introduced some artificial enzymes based on nanomaterials that show significant catalytic activity relative to native enzymes called nanozyme. These nanozymes show superior performance than conventional catalysts and are considered as fascinating candidates for introducing the next generation of biomaterials in various industrial and biomedical fields. Recently, nanozymes have received a great deal of attention in biomedical applications due to their potential properties such as long-term stability, low cost, mass production capability, and controllable catalytic activity. Due to the intrinsic catalytic activity of nanoparticles (NPs) as nanozymes and their ability to be regulated in biomedical processes, this review paper focuses on the in vivo applications of nanozymes in biosensing and therapeutic activities. Despite the challenges and benefits of each approach, this paper attempts to provide an appropriate motivation for the classification of different nanozymes followed by their application in biomedical activities including in vivo biosensing and therapeutic potential in cancer, inflammation and microbial infections. Finally, some ongoing challenges and future perspective of nanozymes in biomedical application were surveyed. In conclusion, this paper may provide useful information regarding the development of nanozymes as promising platforms in biomedical settings due to expedited diagnosis, the advancement of multifactorial therapies and their pronounced stability.

Targets of Vitamin C With Therapeutic Potential for Cardiovascular Disease and Underlying Mechanisms: A Study of Network Pharmacology

Vitamin C (ascorbic acid) is a nutrient used to treat cardiovascular disease (CVD). However, the pharmacological targets of vitamin C and the mechanisms underlying the therapeutic effects of vitamin C on CVD remain to be elucidated. In this study, we used network pharmacology approach to investigate the pharmacological mechanisms of vitamin C for the treatment of CVD. The core targets, major hubs, enriched biological processes, and key signaling pathways were identified. A protein-protein interaction network and an interaction diagram of core target-related pathways were constructed. Three core targets were identified, including phosphatidylinositol 4,5-bisphosphate 3-kinase catalytic subunit alpha isoform, signal transducer and activator of transcription-3 (STAT3), and prothrombin. The GO and KEGG analyses identified top 20 enriched biological processes and signaling pathways involved in the therapeutic effects of vitamin C on CVD. The JAK-STAT, STAT, PD1, EGFR, FoxO, and chemokines signaling pathways may be highly involved in the protective effects of vitamin C against CVD. In conclusion, our bioinformatics analyses provided evidence on the possible therapeutic mechanisms of vitamin C in CVD treatment, which may contribute to the development of novel drugs for CVD.

Thiol/disulfide homeostasis impaired in patients with primary Sjögren's syndrome

Background

Primary Sjögren's syndrome (pSS) is a disease associated with the overexpression of proinflammatory cytokines, and oxidative stress is one of the factors responsible for its etiopathogenesis. This study aimed to investigate the thiol/disulphide homeostasis in pSS patients.

Methods

The study included 68 pSS patients and 69 healthy controls. Thiol/disulphide homeostasis (total thiol, native thiol, and disulphide levels) was measured using the automatic spectrophotometric method developed by Erel and Neselioglu, and the results of the 2 groups were compared.

Results

The gender and age distributions of the pSS and control groups were similar (P = 0.988 and P = 0.065). Total thiol and native thiol levels were lower in the pSS group than in the control group (470.08 ± 33.65 µmol/L vs. 528.21 ± 44.99 µmol/L, P < 0.001, and 439.14 ± 30.67 µmol/L vs. 497.56 ± 46.70 µmol/L, P < 0.001, respectively). There were no differences in disulphide levels between groups [17.00 (range 0.70-217.0) µmol/L vs. 14.95 (range 2.10-40.10) µmol/L, P = 0.195].

Conclusions

It was concluded that the thiol/disulphide balance shifted towards disulphide in patients with pSS.