Zinc Inhibits Phosphate-Induced Vascular Calcification through TNFAIP3-Mediated Suppression of NF-κB

Icariside II Alleviates Chondrocyte Inflammatory Injury by Inhibiting the TNIP2/NF-κB Pathway

Icariside II exerts protective effects against various diseases; however, its specific effects on osteoarthritis (OA) remain unclear. Therefore, in this study, we aimed to investigate the effects of icariside II in an in vitro model of OA and analyze its action mechanisms. We established an in vitro OA model by treating a human chondrocyte cell line (CHON-001) with interleukin (IL)-1β, followed by treatment with different concentrations of icariside II. Cell viability was measured using the methyl thiazolyl tetrazolium assay, and the level of lactate dehydrogenase (LDH) released from cells was determined using the appropriate kit. Tumor necrosis factor (TNF)-α, IL-6, and IL-8 levels were determined via enzyme-linked immunosorbent assay. Flow cytometry was used to assess apoptosis. Apoptosisrelated protein expression levels and TNFAIP3-interacting protein 2 (TNIP2)/nuclear factor (NF)-κB signaling pathway were analyzed via reverse transcription-quantitative polymerase chain reaction and western blotting. Furthermore, TNIP2-small interfering RNA (siRNA) was used to determine whether the TNIP2/NF-κB pathway influences the effects of icariside II on OA. Results indicated that Icariside II did not exert any significant toxic effects on CHON-001 cells. It inhibited IL-1β-induced apoptosis and increase in LDH levels and enhanced the inflammatory response. Additionally, icariside II reversed the IL-1β-induced decrease in TNIP2 levels and increase in NF-κB phosphorylation. TNIP2-siRNA revealed that the TNIP2/NF-κB signaling pathway influenced the alleviating effects of icariside II on OA. In conclusion, our results revealed that icariside II attenuated IL-1β-induced inflammatory injury in chondrocytes by increasing TNIP2 expression and inhibiting NF-κB pathway activation, highlighting its therapeutic potential for OA.

Advances in the mechanisms of vascular calcification in chronic kidney disease

Vascular calcification (VC) is common in patients with advanced chronic kidney disease (CKD).A series of factors, such as calcium and phosphorus metabolism disorders, uremic toxin accumulation, inflammation and oxidative stress and cellular senescence, cause osteoblast-like differentiation of vascular smooth muscle cells, secretion of extracellular vesicles, and imbalance of calcium regulatory factors, which together promote the development of VC in CKD. Recent advances in epigenetics have provided better tools for the investigation of VC etiology and new approaches for finding more accurate biomarkers. These advances have not only deepened our understanding of the pathophysiological mechanisms of VC in CKD, but also provided valuable clues for the optimization of clinical predictors and the exploration of potential therapeutic targets. The aim of this article is to provide a comprehensive overview of the pathogenesis of CKD VC, especially the new advances made in recent years, including the various key factors mentioned above. Through the comprehensive analysis, we expect to provide a solid theoretical foundation and research direction for future studies targeting the specific mechanisms of CKD VC, the establishment of clinical predictive indicators and the development of potential therapeutic strategies.

The pathophysiological functions and therapeutic potential of GPR39: Focus on agonists and antagonists

G protein-coupled receptor 39 (GPR39), a member of the growth hormone-releasing peptide family, exhibits widespread expression across various tissues and demonstrates high constitutive activity, primarily activated by zinc ions. It plays critical roles in cell proliferation, differentiation, survival, apoptosis, and ion transport through the recruitment of Gq/11, Gs, G12/13, and β-arrestin proteins. GPR39 is involved in anti-inflammatory and antioxidant responses, highlighting its diverse pathophysiological functions. Recent discoveries of endogenous ligands have enhanced our understanding of GPR39's physiological roles. Aberrant expression and reactivation of GPR39 have been implicated in a range of diseases, particularly central nervous system disorders, endocrine disruptions, cardiovascular diseases, cancers, and liver conditions. These findings position GPR39 as a promising therapeutic target, with the efficacy of synthetic ligands validated in various in vivo models. Nonetheless, their clinical applicability remains uncertain, necessitating further exploration of novel agonists-especially biased agonists-and antagonists. This review examines the unique residues contributing to the high constitutive activity of GPR39, its endogenous and synthetic ligands, and its pathophysiological implications, aiming to elucidate its pharmacological potential for clinical application in disease treatment.

Research progress on the association between TMAO and vascular calcification in patients with chronic kidney disease

Vascular calcification (VC) is a common complication in patients with chronic kidney disease (CKD) and a major risk factor for increased cardiovascular mortality in patients with CKD. Its pathology and pathogenesis are complex and have not been fully elucidated. Trimethylamine N-oxide (TMAO) is an enteric-borne uremic toxin that has been found to play a role in the progression of VC. This article mainly reviews the metabolism of TMAO, the relationship between TMAO and VC in CKD patients, and possible treatments for TMAO, aiming to further explore the mechanism of VC occurrence in CKD patients and provide potential diagnostic and treatment strategies.

Managing Zinc Supplementation in Hemodialysis Patients: Balancing and Preventing Deficiencies in Serum Copper and Zinc Levels with and Without HIF-PH Inhibitors

BACKGROUND/OBJECTIVES

Zinc supplementation induces metallothionein, leading to reduced serum copper levels. Conversely, serum copper concentrations tend to rise with the use of HIF-PH inhibitors.

METHODS

To establish a safe level of zinc supplementation that avoids copper deficiency, serum copper and zinc concentrations measured every three months were retrospectively analyzed over five years in 50 patients undergoing hemodialysis.

RESULTS

At the initiation of the study, the median (IQR) concentrations were 100 (84.25-109) µg/dL for serum copper and 60.5 (50.5-70) µg/dL for serum zinc. All participants without zinc supplementation exhibited zinc deficiency (<80 µg/dL). After three months, copper deficiency (<71 µg/dL) was observed when serum copper concentrations were <98.6 µg/dL for patients with HIF-PH inhibitors and <90.3 µg/dL for patients without them. Reduced zinc supplementation may be necessary when serum copper falls below 90 µg/dL. Zinc levels remained deficient because supplementation was limited due to concerns about copper deficiency. Lowering the target zinc level to around 80 µg/dL instead of the conventional 80-120 µg/dL may be safer.

CONCLUSIONS

Regular monitoring of both copper and zinc levels, taking place at least every three months, is recommended to adjust zinc supplementation, especially in patients on HIF-PH inhibitors. Copper supplementation should also be considered alongside zinc supplementation to effectively treat hypozincemia.

FHL2 in arterial medial calcification in chronic kidney disease

BACKGROUND

Arterial medial calcification (AMC) is a common complication in individuals with chronic kidney disease (CKD), which can lead to cardiovascular morbidity and mortality. The progression of AMC is controlled by a key transcription factor called runt-related transcription factor 2 (RUNX2), which induces vascular smooth muscle cells (VSMCs) transdifferentiation into an osteogenic phenotype. However, RUNX2 has not been targeted for therapy due to its essential role in bone development. The objective of our study was to discover a RUNX2 coactivator that is highly expressed in arterial VSMCs as a potential therapy for AMC.

METHODS

We employed transcriptomic analysis of human data and an animal reporter system to pinpoint four and a half LIM domains 2 (FHL2) as a potential target. Subsequently, we investigated the mRNA and protein expression patterns of FHL2 in the aortas of both human and animal subjects with CKD. To examine the role of FHL2 in the RUNX2 transcription machinery, we conducted coimmunoprecipitation and chromatin immunoprecipitation experiments. Next, we manipulated FHL2 expression in cultured VSMCs to examine its impact on high phosphate-induced transdifferentiation. Finally, we employed FHL2-null mice to confirm the role of FHL2 in the development of AMC in vivo.

RESULTS

Among all the potential RUNX2 cofactors, FHL2 displays selective expression within the cardiovascular system. In the context of CKD subjects, FHL2 undergoes upregulation and translocation from the cytosol to the nucleus of arterial VSMCs. Once in the nucleus, FHL2 interacts structurally and functionally with RUNX2, acting as a coactivator of RUNX2. Notably, the inhibition of FHL2 expression averts transdifferentiation of VSMCs into an osteogenic phenotype and mitigates aortic calcification in uremic animals, without causing any detrimental effects on the skeletal system.

CONCLUSION

These observations provide evidence that FHL2 is a promising target for treating arterial calcification in patients with CKD.

A Comprehensive Health Screening Program Reveals the Prevalence of and Risk Factors for Age-Related Macular Degeneration: A Cross-Sectional Analysis

Background/Objectives: We investigated the prevalence of age-related macular degeneration (AMD) and associated risk factors in Korean subjects who underwent comprehensive health screening examinations. Methods: This single health screening center-based cross-sectional study included a total of 73,574 consecutive participants older than 30 years who underwent a health screening examination, including fundus photography, between October 2003 and December 2010. Weighted prevalence and risk factors for AMD were evaluated. Logistic regression was used to identify AMD risk factors. Results: The weighted prevalence of AMD was 15.42%, with a prevalence of 3.34% among people in their 30s. Advanced age significantly increased the risk for both early/intermediate AMD (p < 0.001 across the age groups of 40, 50, 60, and 70+ years) and advanced AMD (p <0.001 for the age groups of 60 and 70+ years). The male sex was strongly associated with an increased risk of both early/intermediate and advanced AMD (p < 0.001 for both). Retinal arteriosclerosis, whether low- or high-grade, was linked to early/intermediate AMD (p < 0.001 for both grades), whereas only high-grade arteriosclerosis was linked to advanced AMD (p < 0.001). Additionally, hypertension (p < 0.001), the hepatitis B carrier status (p < 0.001), elevated mean corpuscular volume (p < 0.001), and lower serum uric acid levels (p = 0.014) were associated with early/intermediate AMD. Higher education levels protected against early/intermediate AMD (p = 0.004 for high school graduates, p < 0.001 for ≥college graduates). Higher serum inorganic phosphate levels (p = 0.002) and lower total serum ALB levels (p = 0.005) were significant risk factors for advanced AMD. Conclusions: Korean individuals as young as 30 years old are at risk of AMD. This study newly identified associations between retinal arteriosclerosis and both early/intermediate and advanced AMD, as well as associations between serum inorganic phosphate levels and total ALB levels with advanced AMD.

Zinc Ameliorates High Pi and Ca-Mediated Osteogenic Differentiation of Mesenchymal Stem Cells

Zinc is the second most abundant trace element in the human body, stored mainly in the bones. Zinc is required for bone growth and homeostasis and is also a crucial cofactor for numerous proteins that play key roles in maintaining microstructural integrity and bone remodeling. Bone marrow-derived mesenchymal stem cells (BMSCs) are multipotent progenitors found in the bone marrow stroma and can differentiate along multiple lineage pathways. In this study, we investigated the effect of zinc on the osteogenic differentiation of BMSCs. We stimulated the osteogenic differentiation of BMSCs with high phosphate and Ca-containing osteogenic medium (PiCa) in the presence or absence of zinc. We followed calcification by measuring ECM mineralization, the Ca content of the ECM, mRNA, and the protein expression of the osteo-chondrogenic transcription factor RUNX2 and SOX9 and its targets OCN and ALP. Zinc dose-dependently abolished PiCa-induced ECM mineralization and decreased the expression of RUNX2, SOX9, OCN, and ALP. Serum albumin did not alter the inhibitory effect of zinc on BMSC mineralization. Our further analysis with the zinc-chelator TPEN and ZnCl2 confirmed the specific inhibitory effect of free zinc ions on BMSC mineralization. Zinc inhibited phosphate uptake and PiCa-induced upregulation of the sodium-dependent phosphate cotransporters (PiT-1 and PiT-2). Zinc attenuated the PiCa-induced increase in ROS production. Taken together, these data suggest that zinc inhibits PiCa-induced BMSC calcification by regulating phosphate uptake and ROS production.

From Cells to Plaques: The Molecular Pathways of Coronary Artery Calcification and Disease

Coronary artery calcification (CAC) is a hallmark of atherosclerosis and a critical factor in the development and progression of coronary artery disease (CAD). This review aims to address the complex pathophysiological mechanisms underlying CAC and its relationship with CAD. We examine the cellular and molecular processes that drive the formation of calcified plaques, highlighting the roles of inflammation, lipid accumulation, and smooth muscle cell proliferation. Additionally, we explore the genetic and environmental factors that contribute to the heterogeneity in CAC and CAD presentation among individuals. Understanding these intricate mechanisms is essential for developing targeted therapeutic strategies and improving diagnostic accuracy. By integrating current research findings, this review provides a comprehensive overview of the pathways linking CAC to CAD, offering insights into potential interventions to mitigate the burden of these interrelated conditions.

Composite dietary antioxidant index and abdominal aortic calcification: a national cross-sectional study

PURPOSE

The Composite Dietary Antioxidant Index (CDAI) is a novel, inclusive measure for evaluating the antioxidant potential of diets. We aim to explore the link between the CDAI and abdominal aortic calcification (AAC) in U.S. adults aged ≥ 40 years.

METHODS

This cross-sectional study collected dietary and AAC data for individuals aged ≥ 40 years from the 2013-2014 National Health and Nutrition Examination Survey (NHANES) database. The CDAI was calculated using six dietary antioxidants. AAC was evaluated using a semi-quantitative scoring system known as AAC-24, with an AAC score greater than 6 as severe AAC (SAAC). To examine the association between CDAI and AAC, including SAAC, liner/logistic regression analyses and smooth curve fitting were applied.

RESULTS

A total of 2,640 participants were included in this study, and significant decreases in AAC score and SAAC prevalence were observed with ascending CDAI levels (P < 0.01). After adjusting for confounding factors, a clear link was established between the CDAI and both AAC score (β = -0.083, 95% CI -0.144-0.022, P = 0.008) and SAAC (OR = 0.883, 95% CI 0.806-0.968, P = 0.008), respectively. Further smooth curve fitting indicated a negative correlation between CDAI and both AAC score and SAAC.

CONCLUSIONS

Dietary antioxidant consumption, as quantified by the CDAI, shows an inverse relationship with AAC risk. Additional longitudinal and intervention studies are essential.

Transcriptome analysis provides new insights into the response of canine intestinal epithelial cells treated by sulforaphane: a natural product of cruciferous origin

This study presents a comprehensive transcriptome analysis of canine intestinal epithelial cells following treatment with sulforaphane (SFN), a naturally occurring compound found in cruciferous vegetables with established anti-inflammatory and antioxidant properties. Through high-throughput sequencing, we identified 29,993 genes, among which 1,612 were differentially expressed, with 792 up-regulated and 820 down-regulated in response to SFN treatment. Our analysis revealed significant enrichment of genes in pathways associated with the inflammatory response, lipid metabolism, oxidative stress response, and T-cell mediated immunity, suggesting SFN's potential in modulating these biological processes. Notably, the PPARγ gene, which plays a crucial role in the body's oxidative stress and inflammatory response, was highly up-regulated, indicating its possible centrality in SFN's effects. Gene-gene interaction analysis further supported SFN's role in alleviating inflammation through PPARγ, with key genes in oxidative stress and inflammatory response pathways showing significant correlations with PPARγ. Overall, our findings provide molecular evidence for SFN's protective effects on canine intestinal health, potentially through the modulation of inflammatory and oxidative stress pathways, with PPARγ emerging as a critical mediator.

Multifunctional Bionic Periosteum with Ion Sustained-Release for Bone Regeneration

In this study, a novel bionic periosteum (BP)-bioactive glass fiber membrane (BGFM) is designed. The introduction of magnesium ion (Mg2+) and zinc ion (Zn2+) change the phase separation during the electrospinning (ES) jet stretching process. The fiber's pore structure transitions from connected to closed pores, resulting in a decrease in the rapid release of metal ions while also improving degradation via reducing filling quality. Additionally, the introduction of magnesium (Mg) and zinc (Zn) lead to the formation of negative charged tetrahedral units (MgO4 2- and ZnO4 2-) in the glass network. These units effectively trap positive charged metal ions, further inhibiting ion release. In vitro experiments reveal that the deigned bionic periosteum regulates the polarization of macrophages toward M2 type, thereby establishing a conducive immune environment for osteogenic differentiation. Bioinformatics analysis indicate that BP enhanced bone repair via the JAK-STAT signaling pathway. The slow release of metal ions from the bionic periosteum can directly enhance osteogenic differentiation and vascularization, thereby accelerating bone regeneration. Finally, the bionic periosteum exhibits remarkable capabilities in angiogenesis and osteogenesis, demonstrating its potential for bone repair in a rat calvarial defect model.

Zinc attenuates monocrotaline-induced pulmonary hypertension in rats through upregulation of A20

Pulmonary hypertension (PH) is characterized by excessive proliferation and migration of pulmonary arterial smooth muscle cells (PASMCs), in which inflammatory signaling caused by activation of the NF-κB pathway plays an important role. A20 is an important negative regulator of the NF-κB pathway, and zinc promotes the expression of A20 and exerts a protective effect against various diseases (e.g. COVID19) by inhibiting the inflammatory signaling. The role of A20 and intracellular zinc signaling in PH has been explored, but the extracellular zinc signaling is not well understood, and whether zinc has protective effects on PH is still elusive. Using inductively coupled plasma mass spectrometry (ICP-MS), we studied the alteration of trace elements during the progression of monocrotaline (MCT)-induced PH and found that serum zinc concentration was decreased with the onset of PH accompanied by abnormalities of other three elements, including copper, chromium, and magnesium. Zinc chloride injection with the dosage of 5 mg/kg intraperitoneally partially corrected this abnormality and inhibited the progression of PH. Zinc supplementation induced the expression of A20 in lung tissue and reduce the inflammatory responses. In vitro, zinc supplementation time-dependently upregulated the expression of A20 in PASMCs, therefore correcting the excessive proliferation and migration of cells caused by hypoxia. Using genetically encoded-FRET based zinc probe, we found that these effects of zinc ions are not achieved by entering cells, but most likely by activating cell surface zinc receptor (ZnR/GPR39). These results provide the first evidence of the effectiveness of zinc supplementation in the treatment of PH.

Association between Serum Zinc and All-Cause Mortality in Patients Undergoing Maintenance Hemodialysis: The Osaka Dialysis Complication Study (ODCS)

BACKGROUND/OBJECTIVES

Zinc is an essential microelement, and its deficiency is common in patients undergoing hemodialysis. However, the association between serum zinc and mortality in these patients remains unclear. The aim of this study was to explore the possible association between serum zinc levels and all-cause mortality in prevalent patients with kidney failure on maintenance hemodialysis.

METHODS

This was a prospective cohort study of maintenance hemodialysis patients followed up for 5 years. The key exposure was serum zinc level measured at baseline, and the outcome was all-cause mortality. Their association was analyzed using Cox proportional hazard models.

RESULTS

Among 1662 eligible patients selected for this analysis, 468 (28%) died. Lower serum zinc levels were associated with a higher risk for mortality, independent of the major demographic factors and factors including mineral and bone disorder and renal anemia. However, this association was no longer significant when adjusted for serum albumin. Because there was a close correlation between serum zinc and albumin levels, we performed further analyses in which participants were categorized into four groups by median serum zinc (68 µg/dL) and albumin (3.7 g/dL) levels. In the lower serum albumin groups, risk of death was significantly higher in those with lower zinc than those with higher zinc levels, whereas such a difference was not significant in the high serum albumin groups.

CONCLUSIONS

In patients undergoing maintenance hemodialysis with lower serum albumin levels, a lower serum zinc level was associated with a higher risk of mortality.

Accelerated calciprotein crystallization time (T50) is correlated with impaired lung diffusion capacity in systemic sclerosis

Background

Systemic sclerosis (SSc) is a complex auto-immune disease characterized by vascular damage, inflammation, fibrosis and calcinosis, where pulmonary involvement is the leading cause of mortality. Calciprotein particles (CPPs) are increasingly formed upon disbalance of the physiological mineral buffering system and induce pro-inflammatory effects. This exploratory study investigated whether functional indicators of the endogenous mineral buffering system are dysregulated in SSc and linked to disease activity.

Methods

T50 (calciprotein crystallization test or serum calcification propensity) and hydrodynamic radius of secondary CPPs (CPP2) were determined in serum samples from 78 SSc patients and 44 controls without SSc, and were associated with disease activity markers of SSc.

Results

T50 was reduced and CPP2 radius was increased in SSc patients as compared to controls, indicating a deranged mineral buffering system. This was accompanied by slightly higher serum phosphate and PTH levels in SSc patients, while iFGF23 was not significantly modified. Longitudinally, all parameters remained unchanged over time in SSc patients, only iFGF23 increased. While the modified Rodnan skin score showed some inconsistent correlations with mineral buffering indicators, their association was not independent of other factors. However, lower T50 was significantly correlated to reduced lung diffusion capacity and this association remained significant in a multivariate linear regression model.

Conclusion

This study provides indications for a disturbed mineral buffering system in SSc. Increased serum calcification propensity (lower T50) is correlated with impaired lung diffusion capacity, suggesting a possible role of deranged mineral buffering in disease progression. Further studies are required to confirm these observations in larger cohorts and to investigate a putative functional relevance.

Key regulators of vascular calcification in chronic kidney disease: Hyperphosphatemia, BMP2, and RUNX2

Vascular calcification is quite common in patients with end-stage chronic kidney disease and is a major trigger for cardiovascular complications in these patients. These complications significantly impact the survival rate and long-term prognosis of individuals with chronic kidney disease. Numerous studies have demonstrated that the development of vascular calcification involves various pathophysiological mechanisms, with the osteogenic transdifferentiation of vascular smooth muscle cells (VSMCs) being of utmost importance. High phosphate levels, bone morphogenetic protein 2 (BMP2), and runt-related transcription factor 2 (RUNX2) play crucial roles in the osteogenic transdifferentiation process of VSMCs. This article primarily reviews the molecular mechanisms by which high phosphate, BMP2, and RUNX2 regulate vascular calcification secondary to chronic kidney disease, and discusses the complex interactions among these factors and their impact on the progression of vascular calcification. The insights provided here aim to offer new perspectives for future research on the phenotypic switching and osteogenic transdifferentiation of VSMCs, as well as to aid in optimizing clinical treatment strategies for this condition, bearing significant clinical and scientific implications.

Association of serum zinc with mineral stress in chronic kidney disease

Background

The excessive cardiovascular mortality of patients with chronic kidney disease (CKD) could be linked to mineral stress, the biological consequence of calcium-phosphate nanoparticle exposure. This study investigated whether zinc is associated with mineral stress markers in CKD.

Methods

Zinc and T50 (serum calcification propensity) as well as hydrodynamic radius of secondary calciprotein particles (CPP2) were measured in blood donors and CKD patients with/out dialysis.

Results

Serum zinc concentrations and T50 were reduced, while CPP2 radius was increased in CKD patients. Serum zinc levels positively correlated with T50 and inversely correlated with CPP2 radius. In a hierarchical linear regression model, T50 was associated with age, calcium, phosphate, magnesium and albumin. Addition of zinc significantly improved prediction of the model, confirming an additional contribution of zinc to T50. Similar observations were made for the association of zinc and CPP2 radius, but spiking experiments indicated that zinc may stronger modify T50 than CPP2 radius. Also, urinary zinc excretion was increased in patients with kidney disease and correlated to T50 and CPP2 radius. Serum zinc further correlated with markers of arterial stiffness in blood donors and CKD patients, but these associations did not remain significant in a multivariate linear regression model.

Conclusions

Reduced serum zinc levels in CKD appear directly linked to lower T50 and associated with larger CPP2 radius. Further studies on the associations of zinc and mineral stress as well as putative therapeutic benefits of zinc supplementation are required.

Association Between Dietary Zinc Intake and Increased Renal Function in US Adults

We aimed to investigate the association between the dietary zinc intake and the risk of albuminuria, low estimated glomerular filtration rate (eGFR), and chronic kidney disease (CKD) in the US general population. This study was a cross-sectional study utilizing the data from the 2003-2018 National Health and Nutrition Examination Survey. Albuminuria was defined as urinary albumin:creatinine ratio (ACR) > 30 mg/g. Low eGFR was defined as an eGFR of less than 60 mL/min/1.73 m2. CKD is characterized by albuminuria or low eGFR. Multivariate logistic regression analysis, subgroup analyses, interaction tests, and restricted cubic spline (RCS) analysis were performed in this study. For 37,195 enrolled participants in this study, the mean dietary zinc intake was 11.85 ± 0.07 mg/day, and the rate of albuminuria, low eGFR, and CKD was 9.37%, 6.68%, and 14.10%, respectively. Participants with a higher dietary zinc intake showed a lower risk of albuminuria, low eGFR, and CKD. In the fully adjusted model, we found that participants in the highest dietary zinc intake quartile had 26% lower odds of the rate of CKD than those in quartile 1. Subgroup analyses showed that dietary zinc intake was positively associated with the risk of low eGFR in participants who were now smokers. The potential nonlinear relationship between dietary zinc intake and the risk of CKD and albuminuria was also revealed. Higher dietary zinc intake was significantly associated with a lower likelihood of CKD, which might be helpful in kidney function protection among the general population.

Comprehensive analysis of hypoxia-related genes in diagnosis and immune infiltration in acute myocardial infarction: based on bulk and single-cell RNA sequencing data

Background

Hypoxia has been found to cause cellular dysfunction and cell death, which are essential mechanisms in the development of acute myocardial infarction (AMI). However, the impact of hypoxia-related genes (HRGs) on AMI remains uncertain.

Methods

The training dataset GSE66360, validation dataset GSE48060, and scRNA dataset GSE163956 were downloaded from the GEO database. We identified hub HRGs in AMI using machine learning methods. A prediction model for AMI occurrence was constructed and validated based on the identified hub HRGs. Correlations between hub HRGs and immune cells were explored using ssGSEA analysis. Unsupervised consensus clustering analysis was used to identify robust molecular clusters associated with hypoxia. Single-cell analysis was used to determine the distribution of hub HRGs in cell populations. RT-qPCR verified the expression levels of hub HRGs in the human cardiomyocyte model of AMI by oxygen-glucose deprivation (OGD) treatment in AC16 cells.

Results

Fourteen candidate HRGs were identified by differential analysis, and the RF model and the nomogram based on 8 hub HRGs (IRS2, ZFP36, NFIL3, TNFAIP3, SLC2A3, IER3, MAFF, and PLAUR) were constructed, and the ROC curves verified its good prediction effect in training and validation datasets (AUC = 0.9339 and 0.8141, respectively). In addition, the interaction between hub HRGs and smooth muscle cells, immune cells was elucidated by scRNA analysis. Subsequently, the HRG pattern was constructed by consensus clustering, and the HRG gene pattern verified the accuracy of its grouping. Patients with AMI could be categorized into three HRG subclusters, and cluster A was significantly associated with immune infiltration. The RT-qPCR results showed that the hub HRGs in the OGD group were significantly overexpressed.

Conclusion

A predictive model of AMI based on HRGs was developed and strongly associated with immune cell infiltration. Characterizing patients for hypoxia could help identify populations with specific molecular profiles and provide precise treatment.

Target analysis and identification of curcumin against vascular calcification

To investigate the mechanism of curcumin (CUR) on vascular calcification (VC), we screen for common targets of CUR and atherosclerosis and verify the targets genes in vivo and in vitro experiments. The common targets of CUR and AS were screened and obtained using different databases. These target genes were analyzed by GO and KEGG pathway enrichment analysis. PPI network analysis was performed and to analyze the key targets. A rat VC model was constructed and CUR was fed for three weeks. The changes of vascular structure and calcium salt deposition were observed in H&E and Von Kossa staining. Further, the expression of these target proteins was detected in the primary VSMCs of VC. The 31 common targets were obtained. GO functional enrichment analysis obtained 1284 terms and KEGG pathway enriched 66 pathways. The key genes were identified in the cytoHubba plugin. The molecular docking analysis showed that CUR bound strongly to EGFR, STAT3 and BCL2. The animal experiments showed the deposition calcium salt reduced by the CUR administration. These proteins BMP2, RUNX2, EGFR, STAT3 and BAX expression were upregulated in VC group and CUR attenuated the upregulated expression. The signal protein Akt and p65 expression increased in VC group and decreased in CUR group. We identified some common target genes of CUR and AS and identified these key genes. The anti-VC effect of CUR was associated with the inhibition of upregulation of EGFR, STAT3 and RUNX2 expression in VSMCs.

The Role of Zinc in Developed Countries in Pediatric Patients: A 360-Degree View

Zinc is an important trace element for growth and health at pediatric ages. Zinc is fundamental in inflammatory pathways, oxidative balance, and immune function. Zinc exhibits anti-inflammatory properties by modulating Nuclear Factor-kappa (NF-κB) activity and reducing histamine release from basophils, leukocytes, and mast cells. Furthermore, its antioxidant activity protects against oxidative damage and chronic diseases. Finally, zinc improves the ability to trigger effective immune responses against pathogens by contributing to the maturation of lymphocytes, the production of cytokines, and the regulation of apoptosis. Given these properties, zinc can be considered an adjunctive therapy in treating and preventing respiratory, nephrological, and gastrointestinal diseases, both acute and chronic. This review aims to deepen the role and metabolism of zinc, focusing on the role of supplementation in developed countries in pediatric diseases.

Role of Nutrients in Pediatric Non-Dialysis Chronic Kidney Disease: From Pathogenesis to Correct Supplementation

Nutrition management is fundamental for children with chronic kidney disease (CKD). Fluid balance and low-protein and low-sodium diets are the more stressed fields from a nutritional point of view. At the same time, the role of micronutrients is often underestimated. Starting from the causes that could lead to potential micronutrient deficiencies in these patients, this review considers all micronutrients that could be administered in CKD to improve the prognosis of this disease.

The Role of Rosmarinic Acid in the Protection Against Inflammatory Factors in Rats Model With Monocrotaline-Induced Pulmonary Hypertension: Investigating the Signaling Pathway of NFκB, OPG, Runx2, and P-Selectin in Heart

ABSTRACT

Shortness of breath and syncope are common symptoms of right ventricular failure caused by pulmonary arterial hypertension (PAH), which is the result of blockage and increased pressure in the pulmonary arteries. There is a significant amount of evidence supporting the idea that inflammation and vascular calcification (VC) are important factors in PAH pathogenesis. Therefore, we aimed to investigate the features of the inflammatory process and gene expression involved in VC in monocrotaline (MCT)-induced PAH rats. MCT (60 mg/kg, i.p.) was used to induce PAH. Animals were given normal saline or rosmarinic acid (RA) (10, 15, and 30 mg/kg, gavage) for 21 days. An increase in right ventricular systolic pressure was evaluated as confirming PAH. To determine the level of inflammation in lung tissue, pulmonary edema and the total and differential white blood cell counts in the bronchoalveolar lavage fluid were measured. Also, the expression of NFκB, OPG, Runx2, and P-selectin genes was investigated to evaluate the level of VC in the heart. Our experiment showed that RA significantly decreased right ventricular hypertrophy, inflammatory factors, NFκB, Runx2, and P-selectin gene expression, pulmonary edema, total and differential white blood cell count, and increased OPG gene expression. Therefore, our research showed that RA protects against MCT-induced PAH by reducing inflammation and VC in rats.

Novel diagnostic biomarkers related to necroptosis and immune infiltration landscape in acute myocardial infarction

Background

Acute myocardial infarction (AMI) can occur suddenly, which may induce deadly outcomes, and the population suffering from AMI presents a younger trend. Necroptosis, the new cell necrosis type, is associated with the pathogenic mechanisms of diverse cardiovascular diseases (CVDs). Its diagnostic value and molecular mechanisms in AMI are still unclear. Objective: This study focused on determining key necroptosis-related genes as well as immune infiltration in AMI.

Methods

We first examined the GSE66360 dataset for identifying necroptosis-related differentially expressed genes (NRDEGs). Thereafter, GO and functional annotation were performed, then a PPI network was built. In addition, "CIBERSORT" in R was applied in comparing different immune infiltration degrees in AMI compared with control groups. The receiver operating characteristic (ROC) curve was plotted to evaluate whether hub NRDEGs could be used in AMI diagnosis. Associations of immune cells with candidate NRDEGs biomarkers were examined by Spearman analysis. Finally, hub NRDEGs were validated by cell qPCR assays and another two datasets.

Results

A total of 15 NRDEGs were identified and multiple enrichment terms associated with necroptosis were discovered through GO and KEGG analysis. Upon module analysis, 10 hub NRDEGs were filtered out, and the top six hub NRDEGs were identified after ROC analysis. These top six NRDEGs might have a certain effect on modulating immune infiltrating cells, especially for mast cells activated, NK cells activated and neutrophils. Finally, two AMI datasets and qPCR assay came to identical findings.

Conclusion

Our results offer the reliable molecular biomarkers and new perspectives for necroptosis in AMI, which lay a certain foundation for developing novel anti-AMI therapeutic targets.

Gut microbial metabolites SCFAs and chronic kidney disease

The global incidence of Chronic Kidney Disease (CKD) is steadily escalating, with discernible linkage to the intricate terrain of intestinal microecology. The intestinal microbiota orchestrates a dynamic equilibrium in the organism, metabolizing dietary-derived compounds, a process which profoundly impacts human health. Among these compounds, short-chain fatty acids (SCFAs), which result from microbial metabolic processes, play a versatile role in influencing host energy homeostasis, immune function, and intermicrobial signaling, etc. SCFAs emerge as pivotal risk factors influencing CKD's development and prognosis. This paper review elucidates the impact of gut microbial metabolites, specifically SCFAs, on CKD, highlighting their role in modulating host inflammatory responses, oxidative stress, cellular autophagy, the immune milieu, and signaling cascades. An in-depth comprehension of the interplay between SCFAs and kidney disease pathogenesis may pave the way for their utilization as biomarkers for CKD progression and prognosis or as novel adjunctive therapeutic strategies.

Zic family member 3 attenuates oxidative stress-induced vascular smooth muscle cell apoptosis in patients with chronic kidney disease

Neointimal hyperplasia is reportedly essential for arteriovenous fistulas (AVF) in patients undergoing hemodialysis. Oxidative stress is vital in the progression of uremic venous intimal hyperplasia. Studies have suggested that zinc ions obstruct vascular calcification in patients with chronic kidney disease (CKD). Recent studies have shown that the zinc finger protein, Zic family member 3 (ZIC3), is crucial for the earliest cardiovascular progenitors. ZIC3 mutations are associated with congenital heart disease. However, the mechanism of action of ZIC3 in vascular intimal hyperplasia in CKD remains unelucidated. Venous specimens were collected during primary AVF surgery and traumatic amputation, and serum samples were collected from patients with CKD and healthy controls. Mouse vascular smooth muscle cells (VSMCs) were treated with hydrogen peroxide (H2O2) to clarify the role of ZIC3 in CKD. ZIC3 expression was reduced in the veins of patients with uremia and the serum of those with CKD. Zic3 and Bcl2 levels were significantly decreased in mouse VSMCs treated with H2O2·H2O2 inhibited mouse VSMC activity, upregulated Bax, and cleaved caspase 3 expression. Following Zic3 overexpression, Bcl2 expression level and cell viability were elevated, whereas Bax and cleaved caspase 3 expression levels were downregulated. In contrast, Zic3 knockdown yielded the opposite results. Therefore, ZIC3 could be a new therapeutic target in venous neointimal hyperplasia of CKD.

Similarities and Differences of Vascular Calcification in Diabetes and Chronic Kidney Disease

Presently, the mechanism of occurrence and development of vascular calcification (VC) is not fully understood; a range of evidence suggests a positive association between diabetes mellitus (DM) and VC. Furthermore, the increasing burden of central vascular disease in patients with chronic kidney disease (CKD) may be due, at least in part, to VC. In this review, we will review recent advances in the mechanisms of VC in the context of CKD and diabetes. The study further unveiled that VC is induced through the stimulation of pro-inflammatory factors, which in turn impairs endothelial function and triggers similar mechanisms in both disease contexts. Notably, hyperglycemia was identified as the distinctive mechanism driving calcification in DM. Conversely, in CKD, calcification is facilitated by mechanisms including mineral metabolism imbalance and the presence of uremic toxins. Additionally, we underscore the significance of investigating vascular alterations and newly identified molecular pathways as potential avenues for therapeutic intervention.

The Role of the NF-kB Pathway in Intracranial Aneurysms

The pathophysiology of intracranial aneurysms (IA) has been proven to be closely linked to hemodynamic stress and inflammatory pathways, most notably the NF-kB pathway. Therefore, it is a potential target for therapeutic intervention. In the present review, we investigated alterations in the vascular smooth muscle cells (VSMCs), extracellular matrix, and endothelial cells by the mediators implicated in the NF-kB pathway that lead to the formation, growth, and rupture of IAs. We also present an overview of the NF-kB pathway, focusing on stimuli and transcriptional targets specific to IAs, as well as a summary of the current strategies for inhibiting NF-kB activation in IAs. Our report adds to previously reported data and future research directions for treating IAs using compounds that can suppress inflammation in the vascular wall.

Co-Administration of Roxadustat and Zinc Stabilizes Both Serum Copper and Zinc Concentrations in Patients Undergoing Hemodialysis

Patients undergoing hemodialysis often require zinc supplementation owing to hypozincemia, which may reduce serum copper concentrations. However, hypoxia-inducible factor-prolyl hydroxylase inhibitors (HIF-PHIs), which are used to treat renal anemia, have been reported to increase serum copper. Therefore, this study investigates the effectiveness of a combination of HIF-PHIs and zinc for the stabilization of serum copper and zinc concentrations during zinc supplementation for patients undergoing hemodialysis with renal anemia and hypozincemia. The serum zinc and copper concentrations were retrospectively compared over an 8-month period in 20 patients being administered roxadustat (an HIF-PHI) and 20 controls. The changes in concentrations were tracked in participants taking roxadustat who initiated or increased zinc supplementation. The serum zinc concentrations of the participants were significantly higher (p < 0.001) during zinc supplementation, regardless of roxadustat administration. Post-roxadustat, the serum copper concentrations were significantly higher than those pre-roxadustat or in non-roxadustat-treated participants, irrespective of zinc supplementation (p < 0.005). Even post-roxadustat, the serum copper concentrations were significantly lower, with no increase during zinc supplementation (p < 0.040). When zinc supplementation was initiated or increased in participants taking roxadustat, copper and zinc concentrations were normalized. Thus, combining zinc supplementation with roxadustat prevents both an excessive increase in serum copper and a decrease in serum zinc.

Humoral and cellular factors inhibit phosphate-induced vascular calcification during the growth period

Hyperphosphatemia is an independent and non-classical risk factor of cardiovascular disease and mortality in patients with chronic kidney disease (CKD). Increased levels of extracellular inorganic phosphate (Pi) are known to directly induce vascular calcification, but the detailed underlying mechanism has not been clarified. Although serum Pi levels during the growth period are as high as those observed in hyperphosphatemia in adult CKD, vascular calcification does not usually occur during growth. Here, we have examined whether the defence system against Pi-induced vascular calcification can exist during the growth period using mice model. We found that calcification propensity of young serum (aged 3 weeks) was significantly lower than that of adult serum (10 months), possibly due to high fetuin-A levels. In addition, when the aorta was cultured in high Pi medium in vitro, obvious calcification was observed in the adult aorta but not in the young aorta. Furthermore, culture in high Pi medium increased the mRNA level of tissue-nonspecific alkaline phosphatase (TNAP), which degrades pyrophosphate, only in the adult aorta. Collectively, our findings indicate that the aorta in growing mouse may be resistant to Pi-induced vascular calcification via a mechanism in which high serum fetuin-A levels and suppressed TNAP expression.

Role of inflammation and immunity in vascular calcification: a bibliometric and visual analysis, 2000-2022

Background

In recent years, a great deal of research has been done on vascular calcification (VC), and inflammation and immunity have been displayed to play important roles in the mechanism of VC. However, to date, no comprehensive or systematic bibliometric analyses have been conducted on this topic.

Methods

Articles and reviews on the roles of inflammation and immunity in VC were obtained from the Web of Science Core Collection on August 5, 2022. Four scientometric software packages-HistCite, CiteSpace, VOSviewer, and R-bibliometrix-were used for the bibliometric and knowledge mapping analyses.

Results

The obtained 1,868 papers were published in 627 academic journals by 9,595 authors of 2,217 institutions from 69 countries. The annual number of publications showed a clear growth trend. The USA and China were the most productive countries. Karolinska Institutet, Harvard University, and the University of Washington were the most active institutions. Stenvinkel P published the most articles, whereas Demer LL received the most citations. Atherosclerosis published the most papers, while Circulation was the most highly cited journal. The largest cluster among the 22 clusters, based on the analysis of co-citations, was osteo-/chondrogenic transdifferentiation. "Vascular calcification," "inflammation," "chronic kidney disease," and "expression" were the main keywords in the field. The keyword "extracellular vesicle" attracted great attention in recent years with the strongest citation burst.

Conclusions

Osteo-/chondrogenic transdifferentiation is the primary research topic in this field. Extracellular vesicles are expected to become a new research focus for exploring the inflammatory and immune mechanisms of VC.

TNFAIP3 interacting protein 2 relieves lipopolysaccharide (LPS)-induced inflammatory injury in endometritis by inhibiting NF-kappaB activation

BACKGROUND

Endometritis seriously affects the health of women, and it is important to identify new targets for its treatment.

OBJECTIVE

This study aimed to explore the role of TNFAIP3 interacting protein 2 (TNIP2) in endometritis through human endometrial epithelial cells (hEECs) stimulated by lipopolysaccharide (LPS).

METHODS

hEECs were induced with LPS to build a cellular model of endometritis. Cell growth and apoptosis were detected by cell counting kit-8 and flow cytometry. The TNIP2 mRNA and protein levels were measured using reverse transcription quantitative polymerase chain reaction (RT-qPCR) and western blot analysis, respectively. The caspase3 activity was calculated using a Caspase3 activity kit. Interleukin (IL)-1β, IL-6, and tumor necrosis factor-alpha (TNF-α) levels were determined by enzyme-linked-immunosorbent-assay. The reactive oxygen species (ROS), lactate dehydrogenase (LDH), catalase (CAT), and superoxide dismutase (SOD) levels were determined using the corresponding kits. Nuclear factor-kappaB (NF-κB) pathway was determined by western blot assay.

RESULTS

TNIP2 was downregulated in the LPS-induced endometritis cell model. Cell viability was reduced, apoptosis was enhanced, and IL-6, IL-1β, and TNF-α levels increased in LPS-induced hEECs. Additionally, LDH activity and ROS concentration were upregulated, whereas CAT and SOD activities were downregulated in LPS-induced hEECs. These results were reversed by TNIP2 overexpression. Moreover, the results hinted that NF-κB was involved in the effects of TNIP2 on the LPS-induced endometritis cell model.

CONCLUSION

TNIP2 alleviated endometritis by inhibiting the NF-κB pathway, suggesting a potential therapeutic target for endometritis.

Hypoxia and panvascular diseases: exploring the role of hypoxia-inducible factors in vascular smooth muscle cells under panvascular pathologies

As an emerging discipline, panvascular diseases are a set of vascular diseases with atherosclerosis as the common pathogenic hallmark, which mostly affect vital organs like the heart, brain, kidney, and limbs. As the major responser to the most common stressor in the vasculature (hypoxia)-hypoxia-inducible factors (HIFs), and the primary regulator of pressure and oxygen delivery in the vasculature-vascular smooth muscle cells (VSMCs), their own multifaceted nature and their interactions with each other are fascinating. Abnormally active VSMCs (e.g., atherosclerosis, pulmonary hypertension) or abnormally dysfunctional VSMCs (e.g., aneurysms, vascular calcification) are associated with HIFs. These widespread systemic diseases also reflect the interdisciplinary nature of panvascular medicine. Moreover, given the comparable proliferative characteristics exhibited by VSMCs and cancer cells, and the delicate equilibrium between angiogenesis and cancer progression, there is a pressing need for more accurate modulation targets or combination approaches to bolster the effectiveness of HIF targeting therapies. Based on the aforementioned content, this review primarily focused on the significance of integrating the overall and local perspectives, as well as temporal and spatial balance, in the context of the HIF signaling pathway in VSMC-related panvascular diseases. Furthermore, the review discussed the implications of HIF-targeting drugs on panvascular disorders, while considering the trade-offs involved.

Pathophysiology and Clinical Impacts of Chronic Kidney Disease on Coronary Artery Calcification

The global prevalence of chronic kidney disease (CKD) has increased in recent years. Adverse cardiovascular events have become the main cause of life-threatening events in patients with CKD, and vascular calcification is a risk factor for cardiovascular disease. Vascular calcification, especially coronary artery calcification, is more prevalent, severe, rapidly progressive, and harmful in patients with CKD. Some features and risk factors are unique to vascular calcification in patients with CKD; the formation of vascular calcification is not only influenced by the phenotypic transformation of vascular smooth muscle cells, but also by electrolyte and endocrine dysfunction, uremic toxin accumulation, and other novel factors. The study on the mechanism of vascular calcification in patients with renal insufficiency can provide a basis and new target for the prevention and treatment of this disease. This review aims to illustrate the impact of CKD on vascular calcification and to discuss the recent research data on the pathogenesis and factors involved in vascular calcification, mainly focusing on coronary artery calcification, in patients with CKD.

Signaling pathways in vascular function and hypertension: molecular mechanisms and therapeutic interventions

Hypertension is a global public health issue and the leading cause of premature death in humans. Despite more than a century of research, hypertension remains difficult to cure due to its complex mechanisms involving multiple interactive factors and our limited understanding of it. Hypertension is a condition that is named after its clinical features. Vascular function is a factor that affects blood pressure directly, and it is a main strategy for clinically controlling BP to regulate constriction/relaxation function of blood vessels. Vascular elasticity, caliber, and reactivity are all characteristic indicators reflecting vascular function. Blood vessels are composed of three distinct layers, out of which the endothelial cells in intima and the smooth muscle cells in media are the main performers of vascular function. The alterations in signaling pathways in these cells are the key molecular mechanisms underlying vascular dysfunction and hypertension development. In this manuscript, we will comprehensively review the signaling pathways involved in vascular function regulation and hypertension progression, including calcium pathway, NO-NOsGC-cGMP pathway, various vascular remodeling pathways and some important upstream pathways such as renin-angiotensin-aldosterone system, oxidative stress-related signaling pathway, immunity/inflammation pathway, etc. Meanwhile, we will also summarize the treatment methods of hypertension that targets vascular function regulation and discuss the possibility of these signaling pathways being applied to clinical work.

B4GALNT3 regulates glycosylation of sclerostin and bone mass

BACKGROUND

Global sclerostin inhibition reduces fracture risk efficiently but has been associated with cardiovascular side effects. The strongest genetic signal for circulating sclerostin is in the B4GALNT3 gene region, but the causal gene is unknown. B4GALNT3 expresses the enzyme beta-1,4-N-acetylgalactosaminyltransferase 3 that transfers N-acetylgalactosamine onto N-acetylglucosaminebeta-benzyl on protein epitopes (LDN-glycosylation).

METHODS

To determine if B4GALNT3 is the causal gene, B4galnt3^-/- mice were developed and serum levels of total sclerostin and LDN-glycosylated sclerostin were analysed and mechanistic studies were performed in osteoblast-like cells. Mendelian randomization was used to determine causal associations.

FINDINGS

B4galnt3^-/- mice had higher circulating sclerostin levels, establishing B4GALNT3 as a causal gene for circulating sclerostin levels, and lower bone mass. However, serum levels of LDN-glycosylated sclerostin were lower in B4galnt3^-/- mice. B4galnt3 and Sost were co-expressed in osteoblast-lineage cells. Overexpression of B4GALNT3 increased while silencing of B4GALNT3 decreased the levels of LDN-glycosylated sclerostin in osteoblast-like cells. Mendelian randomization demonstrated that higher circulating sclerostin levels, genetically predicted by variants in the B4GALNT3 gene, were causally associated with lower BMD and higher risk of fractures but not with higher risk of myocardial infarction or stroke. Glucocorticoid treatment reduced B4galnt3 expression in bone and increased circulating sclerostin levels and this may contribute to the observed glucocorticoid-induced bone loss.

INTERPRETATION

B4GALNT3 is a key factor for bone physiology via regulation of LDN-glycosylation of sclerostin. We propose that B4GALNT3-mediated LDN-glycosylation of sclerostin may be a bone-specific osteoporosis target, separating the anti-fracture effect of global sclerostin inhibition, from indicated cardiovascular side effects.

FUNDING

Found in acknowledgements.

COVID-19-induced neurological symptoms: focus on the role of metal ions

Neurological symptoms are prevalent in both the acute and post-acute phases of coronavirus disease 2019 (COVID-19), and they are becoming a major concern for the prognosis of COVID-19 patients. Accumulation evidence has suggested that metal ion disorders occur in the central nervous system (CNS) of COVID-19 patients. Metal ions participate in the development, metabolism, redox and neurotransmitter transmission in the CNS and are tightly regulated by metal ion channels. COVID-19 infection causes neurological metal disorders and metal ion channels abnormal switching, subsequently resulting in neuroinflammation, oxidative stress, excitotoxicity, neuronal cell death, and eventually eliciting a series of COVID-19-induced neurological symptoms. Therefore, metal homeostasis-related signaling pathways are emerging as promising therapeutic targets for mitigating COVID-19-induced neurological symptoms. This review provides a summary for the latest advances in research related to the physiological and pathophysiological functions of metal ions and metal ion channels, as well as their role in COVID-19-induced neurological symptoms. In addition, currently available modulators of metal ions and their channels are also discussed. Collectively, the current work offers a few recommendations according to published reports and in-depth reflections to ameliorate COVID-19-induced neurological symptoms. Further studies need to focus on the crosstalk and interactions between different metal ions and their channels. Simultaneous pharmacological intervention of two or more metal signaling pathway disorders may provide clinical advantages in treating COVID-19-induced neurological symptoms.

Signaling pathway mechanisms of neurological diseases induced by G protein-coupled receptor 39

BACKGROUND

G protein-coupled receptor 39 (GPR39) is a transmembrane zinc receptor with two splice variants, which belongs to the G-protein-coupled receptor growth hormone-releasing peptide family. Its expression is induced by zinc, which activates GPR39, and its activation mediates cell proliferation, ion homeostasis, and anti-inflammatory, antioxidant, and other pathophysiological effects via different signaling pathways.

AIMS

The article reviews the latest literature in this field. In particular, the role of GPR39 in nervous system is discussed.

MATERIALS AND METHODS

GPR39 can be a promising target in neurological diseases for targeted therapy, which will help doctors overcome the associated problems.

DISCUSSION

GPR39 is expressed in vivo at several sites. Increasing evidence suggests that GPR39 plays an important role as a neuroprotective agent in vivo and regulates various neurological functions, including neurodegeneration, neuroelectrophysiology, and neurovascular homeostasis.

CONCLUSION

This review aims to provide an overview of the functions, signal transduction pathways, and pathophysiological role of GPR39 in neurological diseases and summarize the GPR39 agonists that have been identified in the recent years.

L-shaped association between dietary zinc intake and the risk of developing cardiovascular disease in Chinese adults: A cohort study

Background

Although the association of zinc (Zn) with cardiovascular disease (CVD) has been studied, no consensus has been reached on this relationship, particularly dietary Zn intake. The purpose of this study was to assess the effect of dietary Zn intake on the risk of CVD and to analyze whether this effect varied according to zinc consumption using representative data from China.

Methods

11,470 adults from the China Health and Nutrition Survey (CHNS) were eventually enrolled. The dietary information was collected by the 3 day 24-h dietary recalls combined with dietary weighting method. CVD was defined as participants with self-reported physician-diagnosed apoplexy and/or myocardial infarction during the follow-up. Cox regression was used to calculate the hazard ratios (HRs) of CVD with 95% confidence intervals. Restricted cubic spline function plus Cox regression was used to visualize the influence trend of dietary Zn intake on new-onset CVD and to test whether this trend is linear. 2-segment Cox regression was established to address the nonlinear trend.

Results

431 participants developed CVD, including 262 strokes and 197 myocardial infarctions. Compared with the lowest quintile (Q1), the adjusted hazard ratios and 95% confidence interval (CI) of CVD in Q2 to Q5 of dietary Zn intake were 0.72 (0.54, 0.97), 0.59 (0.42, 0.81), 0.50 (0.34, 0.72) and 0.44 (0.27, 0.71), respectively. The influence trend of dietary Zn intake on new-onset CVD was nonlinear and L-shaped. When dietary Zn intake <13.66 mg/day, increased dietary Zn intake was significantly associated with decreased risk of developing CVD (HR = 0.87, 95% CI: 0.82-0.92, p-value <0.0001).

Conclusion

An L-shaped trend was observed between dietary Zn intake and the risk of developing CVD, indicating that dietary Zn intake should be improved moderately, but not excessively, for the benefit of cardiovascular disease.

Zinc Supplementation Induced Transcriptional Changes in Primary Human Retinal Pigment Epithelium: A Single-Cell RNA Sequencing Study to Understand Age-Related Macular Degeneration

Zinc supplementation has been shown to be beneficial to slow the progression of age-related macular degeneration (AMD). However, the molecular mechanism underpinning this benefit is not well understood. This study used single-cell RNA sequencing to identify transcriptomic changes induced by zinc supplementation. Human primary retinal pigment epithelial (RPE) cells could mature for up to 19 weeks. After 1 or 18 weeks in culture, we supplemented the culture medium with 125 µM added zinc for one week. RPE cells developed high transepithelial electrical resistance, extensive, but variable pigmentation, and deposited sub-RPE material similar to the hallmark lesions of AMD. Unsupervised cluster analysis of the combined transcriptome of the cells isolated after 2, 9, and 19 weeks in culture showed considerable heterogeneity. Clustering based on 234 pre-selected RPE-specific genes divided the cells into two distinct clusters, we defined as more and less differentiated cells. The proportion of more differentiated cells increased with time in culture, but appreciable numbers of cells remained less differentiated even at 19 weeks. Pseudotemporal ordering identified 537 genes that could be implicated in the dynamics of RPE cell differentiation (FDR < 0.05). Zinc treatment resulted in the differential expression of 281 of these genes (FDR < 0.05). These genes were associated with several biological pathways with modulation of ID1/ID3 transcriptional regulation. Overall, zinc had a multitude of effects on the RPE transcriptome, including several genes involved in pigmentation, complement regulation, mineralization, and cholesterol metabolism processes associated with AMD.

Clinical Significance of Trace Element Zinc in Patients with Chronic Kidney Disease

The trace element zinc is essential for diverse physiological processes in humans. Zinc deficiency can impair growth, skin reproduction, immune function, maintenance of taste, glucose metabolism, and neurological function. Patients with chronic kidney disease (CKD) are susceptible to zinc deficiency, which is associated with erythropoiesis-stimulating agent (ESA) hypo-responsive anemia, nutritional problems, and cardiovascular diseases as well as non-specific symptoms such as dermatitis, prolonged wound healing, taste disturbance, appetite loss, or cognitive decline. Thus, zinc supplementation may be useful for the treatment of its deficiency, although it often causes copper deficiency, which is characterized by several severe disorders including cytopenia and myelopathy. In this review article, we mainly discuss the significant roles of zinc and the association between zinc deficiency and the pathogenesis of complications in patients with CKD.

Vascular calcification: Molecular mechanisms and therapeutic interventions

Vascular calcification (VC) is recognized as a pathological vascular disorder associated with various diseases, such as atherosclerosis, hypertension, aortic valve stenosis, coronary artery disease, diabetes mellitus, as well as chronic kidney disease. Therefore, it is a life-threatening state for human health. There were several studies targeting mechanisms of VC that revealed the importance of vascular smooth muscle cells transdifferentiating, phosphorous and calcium milieu, as well as matrix vesicles on the progress of VC. However, the underlying molecular mechanisms of VC need to be elucidated. Though there is no acknowledged effective therapeutic strategy to reverse or cure VC clinically, recent evidence has proved that VC is not a passive irreversible comorbidity but an active process regulated by many factors. Some available approaches targeting the underlying molecular mechanism provide promising prospects for the therapy of VC. This review aims to summarize the novel findings on molecular mechanisms and therapeutic interventions of VC, including the role of inflammatory responses, endoplasmic reticulum stress, mitochondrial dysfunction, iron homeostasis, metabolic imbalance, and some related signaling pathways on VC progression. We also conclude some recent studies on controversial interventions in the clinical practice of VC, such as calcium channel blockers, renin-angiotensin system inhibitions, statins, bisphosphonates, denosumab, vitamins, and ion conditioning agents.

ACADL Promotes the Differentiation of Goat Intramuscular Adipocytes

Intramuscular fat (IMF) deposits help improve meat quality such as marbling, juicy, flavor and tenderness. Long-chain acyl-CoA dehydrogenase (ACADL) is a key enzyme for catalyzing fatty acid oxidation, and studies have shown ACADL is involved in the deposition and differentiation of intramuscular adipocytes. However, the effect of ACADL on intramuscular adipocytes differentiation in goats needs further study. In this study, to explore the mechanism of ACADL on the development of goat intramuscular adipocytes, we constructed an over-expression plasmids and a SI-RNA of ACADL to explore the function of ACADL on the development of goat IMF. It was found that overexpression of ACADL promoted the differentiation of goat intramuscular adipocytes, and promoted the expression of fat cell differentiation marker genes lipoprotein lipase (LPL), peroxisome proliferator activated receptor gamma (PPARγ), APETALA-2-like transcription factor gene (AP2), CCAT enhancer binding protein (CEBPα), preadipocyte Factor 1 (Pref-1) and CCAT enhancer binding protein (CEBPβ), and the opposite trend occurred after interference. In addition, we screened of this related tumor necrosis factor (TNF) signaling pathway by RNA-Seq. So, we validate the signaling pathway with inhibitor of TNF signaling pathway. In summary, these results indicate that ACADL promotes intramuscular adipocytes differentiation through activation TNF signaling pathway. This study provides an important basis for the mechanism of IMF development.

Association between zinc deficiency and aorta stiffness in non-diabetic hemodialysis patients

OBJECTIVES

Zinc deficiency (Zn < 60 μg/dL) is known to play an important role for vascular calcification. However, little data is available regarding the association between zinc deficiency and aorta stiffness in dialysis patients. Thus, we studied the relationship between zinc deficiency and aorta stiffness in non-diabetic hemodialysis (HD) patients.

METHODS

Of 150 patients receiving maintenance HD at our hospital, we included 79 non-diabetic HD patients (age: 70±11 years, 49 men) after excluding 71 diabetic HD patients. Zinc deficiency was defined as Zn <60 μg/dL during pre-HD blood sampling. The association between zinc deficiency and aorta stiffness was analyzed. Aorta stiffness was evaluated as brachial-ankle pulse wave velocity (baPWV). Other surrogate markers for cardiovascular complications were also measured.

RESULTS

The zinc deficiency group (ZD group) included 45 patients (57.0%). Compared to the zinc non-deficiency group (ZND group), patients with ZD group were significantly older, higher levels of CRP and hypoalbuminemia. Moreover, they had significantly higher levels of baPWV, and lower levels of ankle-brachial pressure index (ABI) (p<0.05). After adjusting for hypoalbuminemia, and CRP, multivariate analysis showed that age and zinc level were independent predictors of baPWV.

CONCLUSION

The study suggested that zinc deficiency may be an independent risk factor for aorta stiffness, even after adjusting for malnutrition and inflammation.

Benefits and risks of essential trace elements in chronic kidney disease: a narrative review

Background and Objective

Chronic kidney disease (CKD) is an important public health concern. With the decline of renal function, CKD patients gradually progress to end-stage kidney disease and need to undergo dialysis or kidney transplantation to maintain life, bringing a heavy economic burden to the family and society. Therefore, it is necessary to effectively prevent and delay the progression of CKD. Essential trace elements play an indispensable role in CKD, and the objective of this study is to systematically review their benefits in the disease and summarize the risks of their excess.

Methods

The keywords "trace elements", "chronic kidney disease", "dialysis", "inflammation", and "fibrosis" and their combinations were used to search for relevant literature published in the PubMed database and Web of Science. We then summarized the role of trace element abnormalities in CKD patients in anemia, oxidative stress, inflammation, and chronic fibrosis, and the risk of their excess.

Key Content and Findings

Imbalance of essential trace elements is a common complication of CKD and a risk factor for CKD progression, cardiovascular events, and death. This article reviews the effects of essential trace elements (iron, zinc, selenium, copper, iodine, and manganese) on CKD. We analyze literature and discuss the advantages and disadvantages of various essential trace elements.

Conclusions

Research shows CKD patients have an imbalance of essential trace elements, and treatment based on these is an important direction for future exploration. A knowledge of the homeostasis of trace elements is important to improving the prognosis of CKD patients and delaying the progression of the disease.

The molecular mechanisms and intervention strategies of mitophagy in cardiorenal syndrome

Cardiorenal syndrome (CRS) is defined as a disorder of the heart and kidney, in which acute or chronic injury of one organ may lead to acute or chronic dysfunction of the other. It is characterized by high morbidity and mortality, resulting in high economic costs and social burdens. However, there is currently no effective drug-based treatment. Emerging evidence implicates the involvement of mitophagy in the progression of CRS, including cardiovascular disease (CVD) and chronic kidney disease (CKD). In this review, we summarized the crucial roles and molecular mechanisms of mitophagy in the pathophysiology of CRS. It has been reported that mitophagy impairment contributes to a vicious loop between CKD and CVD, which ultimately accelerates the progression of CRS. Further, recent studies revealed that targeting mitophagy may serve as a promising therapeutic approach for CRS, including clinical drugs, stem cells and small molecule agents. Therefore, studies focusing on mitophagy may benefit for expanding innovative basic research, clinical trials, and therapeutic strategies for CRS.

Serum Calcification Propensity Represents a Good Biomarker of Vascular Calcification: A Systematic Review

Vascular calcification contributes to cardiovascular morbidity and mortality. A recently developed serum calcification propensity assay is based on the half-transformation time (T50) from primary calciprotein particles (CPPs) to secondary CPPs, reflecting the serum’s endogenous capacity to prevent calcium phosphate precipitation. We sought to identify and review the results of all published studies since the development of the T50-test by Pasch et al. in 2012 (whether performed in vitro, in animals or in the clinic) of serum calcification propensity. To this end, we searched PubMed, Elsevier EMBASE, the Cochrane Library and Google Scholar databases from 2012 onwards. At the end of the selection process, 57 studies were analyzed with regard to the study design, sample size, characteristics of the study population, the intervention and the main results concerning T50. In patients with primary aldosteronism, T50 is associated with the extent of vascular calcification in the abdominal aorta. In chronic kidney disease (CKD), T50 is associated with the severity and progression of coronary artery calcification. T50 is also associated with cardiovascular events and all-cause mortality in CKD patients, patients on dialysis and kidney transplant recipients and with cardiovascular mortality in patients on dialysis, kidney transplant recipients, patients with ischemic heart failure and reduced ejection fraction, and in the general population. Switching from acetate-acidified dialysate to citrate-acidified dialysate led to a longer T50, as did a higher dialysate magnesium concentration. Oral administration of magnesium (in CKD patients), phosphate binders, etelcalcetide and spironolactone (in hemodialysis patients) was associated with a lower serum calcification propensity. Serum calcification propensity is an overall marker of calcification associated with hard outcomes but is currently used in research projects only. This assay might be a valuable tool for screening serum calcification propensity in at-risk populations (such as CKD patients and hemodialyzed patients) and, in particular, for monitoring changes over time in T50.

Study on the Effects of Different Doses of Dahuang Zhechong Pills on the Ubiquitin Proteasome Pathway/Nuclear Factor-κB in Rats with Atherosclerosis and Its Mechanism

In order to investigate the effects of different doses of Dahuang Zhechong pills on the ubiquitin proteasome pathway/nuclear factor-κB (UPP-NF-κB) in rats with atherosclerosis (AS), 58-week-old male Wistar rats were selected and randomly divided into the normal group, model group, control group, low-dose group, and high-dose group. The model group and the drug group are given intraperitoneal injections of vitamins, and the model group and the drug group are given a high-fat diet. Rats in the low-dose group and high-dose group are given low-dose and high-dose Dahuang Zhechong pill lavage solution, respectively. Besides, the control group is given simvastatin solution by gavage, and intervention is performed once a day for 12 weeks. Ubiquitin (Ub) protein expression, ubiquitin activase (UBE1), nuclear factor-κB, nuclear inhibitory factor-κB (IκB) gene expression, total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and serum tumor necrosis factor-α (TNF-α) are compared. The experimental result shows that Dahuang Zhechong pills can reduce inflammation and prevent and treat AS by blocking the activation of the UPP/NF-κB signaling pathway and can be used as a proteasome inhibitor in the clinical treatment of AS.

Periostin Augments Vascular Smooth Muscle Cell Calcification via β-Catenin Signaling

Medial vascular calcification is common in chronic kidney disease (CKD) and is closely linked to hyperphosphatemia. Vascular smooth muscle cells (VSMCs) can take up pro-calcific properties and actively augment vascular calcification. Various pro-inflammatory mediators are able to promote VSMC calcification. In this study, we investigated the effects and mechanisms of periostin, a matricellular signaling protein, in calcifying human VSMCs and human serum samples. As a result, periostin induced the mRNA expression of pro-calcific markers in VSMCs. Furthermore, periostin augmented the effects of β-glycerophosphate on the expression of pro-calcific markers and aggravated the calcification of VSMCs. A periostin treatment was associated with an increased β-catenin abundance as well as the expression of target genes. The pro-calcific effects of periostin were ameliorated by WNT/β-catenin pathway inhibitors. Moreover, a co-treatment with an integrin αvβ3-blocking antibody blunted the pro-calcific effects of periostin. The silencing of periostin reduced the effects of β-glycerophosphate on the expression of pro-calcific markers and the calcification of VSMCs. Elevated serum periostin levels were observed in hemodialysis patients compared with healthy controls. These observations identified periostin as an augmentative factor in VSMC calcification. The pro-calcific effects of periostin involve integrin αvβ3 and the activation of the WNT/β-catenin pathway. Thus, the inhibition of periostin may be beneficial to reduce the burden of vascular calcification in CKD patients.