The impact of aging on neutrophil functions and the contribution to periodontitis

The increasing aging population and aging-associated diseases have become a global issue for decades. People over 65 show an increased prevalence and greater severity of periodontitis, which poses threats to overall health. Studies have demonstrated a significant association between aging and the dysfunction of neutrophils, critical cells in the early stages of periodontitis, and their crosstalk with macrophages and T and B lymphocytes to establish the periodontal lesion. Neutrophils differentiate and mature in the bone marrow before entering the circulation; during an infection, they are recruited to infected tissues guided by the signal from chemokines and cytokines to eliminate invading pathogens. Neutrophils are crucial in maintaining a balanced response between host and microbes to prevent periodontal diseases in periodontal tissues. The impacts of aging on neutrophils' chemotaxis, anti-microbial function, cell activation, and lifespan result in impaired neutrophil functions and excessive neutrophil activation, which could influence periodontitis course. We summarize the roles of neutrophils in periodontal diseases and the aging-related impacts on neutrophil functional responses. We also explore the underlying mechanisms that can contribute to periodontitis manifestation in aging. This review could help us better understand the pathogenesis of periodontitis, which could offer novel therapeutic targets for periodontitis.

Traditional Chinese patent medicine Zhixiong Capsule (ZXC) alleviated formed atherosclerotic plaque in rat thoracic artery and the mechanism investigation including blood-dissolved-component-based network pharmacology analysis and biochemical validation

ETHNOPHARMACOLOGICAL RELEVANCE

Chinese patent medicine Zhixiong Capsule (ZXC) is the equal mixture of the extract of leech, Ligusticum chuanxiong Hort., Salvia miltiorrhiza Bunge, Leonurus japonicus Houtt., and Pueraria lobate (Willd.) Ohwi, which have been long used against inflammation, hyperlipidemia or blood stasis. In our previous study, ZXC showed good efficacy in preventing atherosclerosis (AS) plaque formation in rabbits.

AIM OF THE STUDY

In actual clinic practice, patients are more likely to receive treatments after AS plaque formation. Therefore, the efficacy of ZXC on formed AS plaques and the underlying mechanisms were further investigated in this study.

MATERIALS AND METHODS

Simvastatin (positive control) and ZXC (420 mg/kg and 840 mg/kg) were administrated to rats which first received long-term high fat diet administration (12 weeks). The blood lipid profiles of rats were monitored during the whole experiment, and the thoracic arteries were collected at the end of experiment for AS assessment (18th week). The blood-dissolved ZXC components were determined using an UPLC-QTOF-MS method, and the attained components were then used for network pharmacology analysis to predict the key ZXC components and targets. At last, the predicted targets were validated by ELISA and western blot methods.

RESULTS

ZXC administration showed good blood lipid-lowering effect by significantly reduced LDL-C and TC levels in rats while significantly increased HDL-C level. Compared with model group, simvastatin, low- and high-dose of ZXC administration decreased the ratio of intimal area and medial area by 81.1%, 71.1% and 71.4%, respectively (p < 0.01), and significantly alleviated collagen deposition and mineralization in rat arteries. It was found by network pharmacology analysis that leech and four components (namely daidzein, 4-methylenemiltirone, isorhamnetin and 2-isopropyl-8-methylphenanthrene-3,4-dione) are vital components for the anti-AS efficacy of ZXC. Combing the results from biochemical validation, IL-4, IL-13, MAPK1, MAPK14, JUN and P53 were confirmed as key targets of ZXC.

CONCLUSION

It could be concluded that ZXC has value as an anti-AS agent in clinical treatment against formed AS plaque at the current application dosage.

Dysfunctional high density lipoprotein failed to rescue the function of oxidized low density lipoprotein-treated endothelial progenitor cells: a novel index for the prediction of HDL functionality

Lipid metabolic disorders play critical roles in atherogenesis. Traditionally, it has been suggested that reduced high density lipoprotein (HDL) levels might be an important morbidity indicator for cardiovascular diseases. Therefore, it has been argued that therapeutically raising HDL levels may reduce atherogenesis in patients with dyslipidemia. However, recent clinical trials to elevate serum HDL levels by pharmacologic approaches failed to demonstrate clinical efficacy. Thus, to investigate the functionality of HDL and to explore the possible clinical relevance as well as to define an effective indicator that can represent HDL function may provide another key and reference to disclose the clinical treatment of dyslipidemia. We analyzed the association between the data of dichlorofluorescein assay (assay the functionality of HDL), the effect of HDL on oxidized low density lipoprotein (oxLDL)-stimulated endothelial progenitor cells (EPCs) in vitro, levels of circulating EPCs, and ex vitro EPC colony forming units of each case, we defined the indicator (relative HDL index (RHDL index) = dichlorofluorescein assay result of each subject/dichlorofluorescein assay reading of our young healthy controls) that may represent functionality of HDL. HDL from healthy adults protected oxLDL-treated EPCs by modulating p38 mitogen-activated protein kinase and Rho activation and by promoting nitric oxide production. HDL from subject with RHDL index ≧2 also failed to restore the functionality of oxLDL-treated EPCs via cell-signaling pathways in vitro. The RHDL index significantly correlated with patients' circulating EPC number or EPC colony forming units ex vivo. In conclusions, we explored the RHDL index as a score to predict a patient's EPC functions in vivo and ex vitro.

Association between circulating oxidized low-density lipoprotein and atherosclerotic cardiovascular disease

Atherosclerosis is a chronic, progressive disease which eventually leads to coronary heart disease (CHD), ischemic stroke and other atherosclerotic cardiovascular disease (ASCVD). Numerous studies have demonstrated an atherogenic role of oxidized low-density lipoprotein (ox-LDL) in the progression of ASCVD. This article briefly reviews the atherogenic mechanism of ox-LDL, the methods of measuring ox-LDL in the circulation, effect of medical therapy and life-style modification on ox-LDL level, and the association between circulating ox-LDL and atherosclerosis, including clinical ASCVD events and subclinical atherosclerosis, in observational studies.

Endocan Levels and Subclinical Atherosclerosis in Patients With Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease of unknown etiology. A major cause of morbidity and mortality in SLE is accelerated atherosclerosis. Endothelial-specific molecule 1 (endocan) is a potential predictor of vascular events and is expressed in response to inflammatory cytokines in endothelial cells. We investigated the relationship between endocan and carotid intima-media thickness (cIMT) as a marker of early atherosclerosis. We included 44 women with SLE and 44 healthy women as controls. Disease severity of SLE was evaluated using the SLE Disease Activity Index. Endocan, C-reactive protein, erythrocyte sedimentation rate (ESR), and lipid panel were measured. The cIMT was 0.70 (range: 0.45-1.20) mm in patients with SLE and 0.40 (0.25-0.60) mm in controls (P < .001). Endocan value was 1.6 ± 0.9 ng/mL in controls and 2.2 ± 1.0 ng/mL in patients with SLE (P = .014). Endocan levels were positively correlated with cIMT (r = .469, P < .001), body mass index (r = .373, P = .013), and ESR (r = .393, P = .008). Endocan level may be associated with subclinical atherosclerosis in SLE. Consequently, endocan levels may be a promising clinical tool for patients with SLE as a guide for preventive strategy.

The biphasic effects of oxidized-low density lipoprotein on the vasculogenic function of endothelial progenitor cells

Late-outgrowth endothelial progenitor cells (EPCs) are stress-resistant and responsible for reparative functions in the cardiovascular system. Oxidized-LDL (oxLDL) plays a critical role in cardiovascular disease pathogenesis. However, it is largely unknown what the impacts of oxLDL are on late-outgrowth EPCs. This study aimed to investigate the concentration-related effects of oxLDL on EPC functions and related angiogenesis, in vitro and in vivo. In this study, early and late-outgrowth EPCs were generated from circulating human mononuclear cells. oxLDL may regulate EPC vasculogenic function via the lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1). Lower concentrations (5 μg/mL) of oxLDL can potentiate EPC tube formation in vitro and in vivo by activating eNOS mechanisms, which are mediated by p38 MAPK- and SAPK/JNK-related pathways. Higher concentrations of oxLDL (10-50 μg/mL) impaired EPC function via the activation of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase pathways and consequent inhibition of eNOS activity, which could be reversed by anti-oxidants (diphenylene iodonium and apocynin) and gp91^phox siRNA. In conclusion, oxLDL has concentration-dependent biphasic effects on human late-outgrowth EPC tube formation in vitro and in vivo.