The Balance of Tissue Inhibitor of Metalloproteinase-1 and Matrix Metalloproteinase-9 in the Autoimmune Inner Ear Disease Patients

Marine Bioactive Peptides: Anti-Photoaging Mechanisms and Potential Skin Protective Effects

Skin photoaging, resulting from prolonged exposure to ultraviolet radiation, is a form of exogenous aging that not only impacts the aesthetic aspect of the skin but also exhibits a strong correlation with the onset of skin cancer. Nonetheless, the safety profile of non-natural anti-photoaging medications and the underlying physiological alterations during the process of photoaging remain inadequately elucidated. Consequently, there exists a pressing necessity to devise more secure interventions involving anti-photoaging drugs. Multiple studies have demonstrated the noteworthy significance of marine biomolecules in addressing safety concerns related to anti-photoaging and safeguarding the skin. Notably, bioactive peptides have gained considerable attention in anti-photoaging research due to their capacity to mitigate the physiological alterations associated with photoaging, including oxidative stress; inflammatory response; the abnormal expression of matrix metalloproteinase, hyaluronidase, and elastase; and excessive melanin synthesis. This review provides a systematic description of the research progress on the anti-photoaging and skin protection mechanism of marine bioactive peptides. The focus is on the utilization of marine bioactive peptides as anti-photoaging agents, aiming to offer theoretical references for the development of novel anti-photoaging drugs and methodologies. Additionally, the future prospects of anti-aging drugs are discussed, providing an initial reference for further research in this field.

Bioinformatic Analysis of the Perilymph Proteome to Generate a Human Protein Atlas

The high complexity of the cellular architecture of the human inner ear and the inaccessibility for tissue biopsy hampers cellular and molecular analysis of inner ear disease. Sampling and analysis of perilymph may present an opportunity for improved diagnostics and understanding of human inner ear pathology. Analysis of the perilymph proteome from patients undergoing cochlear implantation was carried out revealing a multitude of proteins and patterns of protein composition that may enable characterisation of patients into subgroups. Based on existing data and databases, single proteins that are not present in the blood circulation were related to cells within the cochlea to allow prediction of which cells contribute to the individual perilymph proteome of the patients. Based on the results, we propose a human atlas of the cochlea. Finally, druggable targets within the perilymph proteome were identified. Understanding and modulating the human perilymph proteome will enable novel avenues to improve diagnosis and treatment of inner ear diseases.

Hearing restoration and the stria vascularis: evidence for the role of the immune system in hearing restoration

PURPOSE OF REVIEW

This article reviews the current literature regarding the pathogenesis of immune-mediated sensorineural hearing loss, utilizes previously published single-nucleus transcriptional profiles to characterize cytokine and cytokine receptor expression in the adult stria vascularis cell types to support immune system interaction with the stria vascularis and reviews the current literature on immunomodulatory agents currently being used for hearing-restoration treatment.

RECENT FINDINGS

The literature review highlights recent studies that elucidate many cytokines and immune markers, which have been linked to various immune-mediated disease processes that have been observed with sensorineural hearing loss within the stria vascularis and highlights recent publications studying therapeutic targets for these pathways.

SUMMARY

This review highlights the current literature regarding the pathogenesis of immune-mediated hearing loss. The role of cochlear structures in human temporal bones from patients with immune-mediated sensorineural hearing loss are highlighted, and we review cytokine signalling pathways relevant to immune-mediated sensorineural hearing loss and localize genes encoding both cytokine and cytokine receptors involved in these pathways. Finally, we review immunomodulatory therapeutics in light of these findings and point to opportunities for the application of novel therapeutics by targeting these signalling pathways.

Carotid imaging changes and serum IL-1β, sICAM-1, and sVAP-1 levels in benign paroxysmal positional vertigo

Benign paroxysmal positional vertigo (BPPV) is the most common cause of vertigo. This study was performed to evaluate serum levels of inflammatory factors and changes in B-mode carotid ultrasound findings in patients with BPPV. The study population consisted of 90 BPPV patients and 90 age- and sex-matched controls. ELISA was used to compare the levels of inflammatory factors, such as interleukin-1β (IL-1β), tumor necrosis factor-alpha (TNF-α), soluble intercellular adhesion molecule-1 (sICAM-1), prostaglandin-E2 (PG-E2), and soluble vascular adhesion protein-1 (sVAP-1), between BPPV patients and controls. In addition, the results of ultrasonographic imaging to determine carotid intima-media thickness (C-IMT), carotid atheromatous plaque, and vertebral artery stenosis were also compared between the BPPV and control groups. Serum levels of IL-1β, sICAM-1, and sVAP-1 were significantly higher in BPPV patients than controls (P < 0.001, P < 0.05, and P < 0.001, respectively). C-IMT and vertebral artery stenosis were significantly different in BPPV patients compared to controls (both P < 0.05). There were no significant relations between other parameters and BPPV. IL-1β, sICAM-1, and sVAP-1 are potentially associated with the pathogenesis of BPPV, and C-ITM and carotid vertebral stenosis may be useful reference imaging findings for the diagnosis of BPPV.

The inhibition of tumor protein p53 by microRNA-151a-3p induced cell proliferation, migration and invasion in nasopharyngeal carcinoma

A close relation between microRNA-151a-3p (miR-151a-3p) and nasopharyngeal carcinoma (NPC) has been reported, however, the molecular mechanism is still unclear. The aim of the present study was to explore the mechanism in the promotion of miR-151a-3p to NPC progression. The levels of miR-151-3p in several NPC cell lines were detected in order to screen an experimental cell line. MiR-151a-3p mimic and inhibitor were constructed and transfected into 5-8F cells and cell proliferation were detected by Cell Counting Kit-8 (CCK-8). The apoptosis rate, cell migration and invasion were determined by flow cytometry, wound healing and Transwell assays. The predicted target was further verified by luciferase reporter assay. Real-time quantification-PCR and Western blot were carried out for mRNA and protein level analysis. Tumor protein p53 was co-transfected to verify the functions of miR-151a-3p. The miR-151a-3p level in NPC tissues was much higher than that in adjacent tissues. After transfecting cells with miR-151a-3p mimic, the cell proliferation and patients' survival rate were much increased, and this was accompanied by the increase in B-cell lymphoma 2 (Bcl-2) and decreases in Bax and cleaved caspase-3 (P<0.01). Moreover, the migration rate and number of invaded cells were also remarkably increased, however, the miR-151a-3p inhibitor had opposite effects on the 5-8F cells. Noticeably, p53 was revealed as a potential target of miR-151a-3p. Co-transfection of P53 could partially reverse the promotive effects of miR-151a-3p on NPC cell progression. Our data indicated that blocking p53 expression and mediated signal pathways contribute to the positive effects of miR-151a-3p on NPC cell proliferation, migration and invasion.

Autoimmune inner ear disease patient-associated 28-kDa proinflammatory IL-1β fragment results from caspase-7-mediated cleavage in vitro

Interleukin-1β (IL-1β) is a key proinflammatory cytokine involved in the progression of many autoinflammatory and autoimmune diseases, including autoimmune inner ear disease (AIED). IL-1β inhibition has been shown to result in clinical hearing improvement in a small cohort of corticosteroid-resistant patients with AIED. Canonical processing of pro-IL-1β by caspase-1 generates an active 17-kDa fragment, capable of instigating a proinflammatory microenvironment. However, in response to LPS, PBMCs from patients with AIED uniquely express a 28-kDa IL-1β fragment, as compared with PBMCs from control subjects. We synthesized and compared the biologic activity of the 28-kDa fragment to the 17-kDa IL-1β product and the pro-IL-1 31-kDa protein. The 28-kDa IL-1β fragment induces IL-6, TNF-α, and CCL3 in PBMCs. Uniquely, only caspase-7 treatment showed a dose- and time-dependent increase in 28-kDa band generation. Mass spectrometry confirmed the putative caspase-7 cleavage site of pro-IL-1β, which was used to generate the 28-kDa fragment used for PBMC stimulation studies. Collectively, these results provide insight into the function of a poorly understood, processed 28-kDa form of IL-1β in patients with AIED that is uniquely generated by caspase-7 and is capable of activating further downstream proinflammatory cytokines. Further investigation may provide novel pharmacologic targets for the treatment of this rare disease.

Kaempferol attenuates neuroinflammation and blood brain barrier dysfunction to improve neurological deficits in cerebral ischemia/reperfusion rats

Kaempferol has been reported to act as an anti-inflammatory agent in LPS-induced neuroinflammation in vitro and in vivo, but its role in the inflammation after cerebral ischemia/reperfusion (I/R) is unclear. The present study was to investigate the effect of kaempferol on inflammation in ischemic brain tissue and explore its mechanisms in cerebral I/R rats. Cerebral I/R rat model was established by middle cerebral artery occlusion for 60 min and following reperfusion. Kaempferol at doses of 25, 50 and 100 mg/kg was administered for 7 days after cerebral I/R. Kaempferol treatment significantly reduced cerebral infarct volume, attenuated inflammation and blood-brain barrier (BBB) disruption after cerebral I/R, thus improved neurological outcomes at the day 7 after cerebral I/R. Furthermore, the results also showed kaempferol treatment decreased the phosphorylation and nuclear transposition of transcription factor NF-κB p65, thus inhibited expression of various pro-inflammatory proteins. In conclusion, kaempferol attenuates neuroinflammation and blood brain barrier dysfunction to improve neurological deficits in cerebral I/R rats, its mechanism is related to NF-κB pathway.

Up-regulation of COX-2 and mPGES-1 by 27-hydroxycholesterol and 4-hydroxynonenal: A crucial role in atherosclerotic plaque instability

Atherosclerosis is currently understood to be mainly the consequence of a complicated inflammatory process at the different stages of plaque development. Among the several inflammatory molecules involved, up-regulation of the functional cyclooxygenase 2/membrane-bound prostaglandin E synthase 1 (COX-2/mPGES-1) axis plays a key role in plaque development. Excessive production of oxidized lipids, following low-density lipoprotein (LDL) oxidation, is a characteristic feature of atherosclerosis. Among the oxidized lipids of LDLs, the oxysterol 27-hydroxycholesterol (27-OH) and the aldehyde 4-hydroxynonenal (HNE) substantially accumulate in the atherosclerotic plaque, contributing to its progression and instability through a variety of processes. This study shows that 27-OH and HNE promote up-regulation of both the inducible enzymes COX-2 and mPGES-1, leading to increased production of prostaglandin (PG) E₂ and inducible nitric oxide synthase, and the subsequent release of nitric oxide in human promonocytic U937 cells. The study also examined the potential involvement of the functionally coupled COX-2/mPGES-1 in enhancing the production of certain pro-inflammatory cytokines and of matrix metalloproteinase 9 by U937 cells. This enhancement is presumably due to the induction of PGE₂ synthesis, as a result of the up-regulation of the COX-2/mPGES-1, stimulated by the two oxidized lipids, 27-OH and HNE. Induction of PGE₂ synthesis might thus be a mechanism of plaque instability and eventual rupture, contributing to matrix metalloproteinase production by activated macrophages.