Exploring the Prevalence of Tinnitus and Ear-Related Symptoms in China After the COVID-19 Pandemic: Online Cross-Sectional Survey.

BACKGROUND: Tinnitus is a complex and heterogeneous disease that has been identified as a common manifestation of COVID-19. To gain a comprehensive understanding of tinnitus symptoms in individuals following COVID-19 infection, we conducted an online survey called the China Ear Nose and Throat Symptom Survey in the COVID-19 Pandemic (CENTSS) among the Chinese population. OBJECTIVE: Our objective was to investigate tinnitus and ear-related symptoms after COVID-19 infection in the Chinese population, with the aim of providing a solid empirical foundation for improved health care. The findings from CENTSS can contribute to the development of enhanced management strategies for tinnitus in the context of long COVID. By gaining a better understanding of the factors contributing to tinnitus in individuals with COVID-19, health care providers can tailor interventions to address the specific needs of affected patients. Furthermore, this study serves as a basis for research on the long-term consequences of COVID-19 infection and its associated tinnitus symptoms. METHODS: A quantitative, online, cross-sectional survey study design was used to explore the impact of the COVID-19 pandemic on experiences with tinnitus in China. Data were collected through an online questionnaire designed to identify the presence of tinnitus and its impacts. Descriptive statistics were used to analyze individuals' demographic characteristics, COVID-19 infection-related ear symptoms, and the cognitive and emotional implications of tinnitus. Univariable and multivariable logistic regression analyses were used to model the cross-sectional baseline associations between demographic characteristics, noise exposure, educational level, health and lifestyle factors, and the occurrence of tinnitus. RESULTS: Between December 19, 2022, and February 1, 2023, we obtained responses from 1262 Chinese participants representing 24 regions, with an average age of 37 years. Among them, 540 patients (42.8%) reported experiencing ear-related symptoms after COVID-19 infection. Only 114 (9%) of these patients sought medical attention specifically for their ear symptoms, while 426 (33.8%) did not seek hospital care. Tinnitus emerged as the most prevalent and impactful symptom among all ear-related symptoms experienced after COVID-19 infection. Of the respondents, female participants (688/888, 77.78%), younger individuals (<30 years), individuals with lower education levels, participants residing in western China, and those with a history of otolaryngology diseases were more likely to develop tinnitus following COVID-19 infection. CONCLUSIONS: In summary, tinnitus was identified as the most common ear-related symptom during COVID-19 infection. Individuals experiencing tinnitus after COVID-19 infection were found to have poorer cognitive and emotional well-being. Different ear-related symptoms in patients post-COVID-19 infection may suggest viral invasion of various parts of the ear. It is therefore crucial to monitor and manage hearing-related changes resulting from COVID-19 as clinical services resume.

Renal lipid accumulation and aging linked to tubular cells injury via ANGPTL4.

Renal tubular epithelial cells are vulnerable to stress-induced damage, including excessive lipid accumulation and aging, with ANGPTL4 potentially playing a crucial bridging role between these factors. In this study, RNA-sequencing was used to identify a marked increase in ANGPTL4 expression in kidneys of diet-induced obese and aging mice. Overexpression and knockout of ANGPTL4 in renal tubular epithelial cells (HK-2) was used to investigate the underlying mechanism. Subsequently, ANGPTL4 expression in plasma and kidney tissues of normal young controls and elderly individuals was analyzed using ELISA and immunohistochemical techniques. RNA sequencing results showed that ANGPTL4 expression was significantly upregulated in the kidney tissue of diet-induced obesity and aging mice. In vitro experiments demonstrated that overexpression of ANGPTL4 in HK-2 cells led to increased lipid deposition and senescence. Conversely, the absence of ANGPTL4 appears to alleviate the impact of free fatty acids (FFA) on aging in HK-2 cells. Additionally, aging HK-2 cells exhibited elevated ANGPTL4 expression, and stress response markers associated with cell cycle arrest. Furthermore, our clinical evidence revealed dysregulation of ANGPTL4 expression in serum and kidney tissue samples obtained from elderly individuals compared to young subjects. Our study findings indicate a potential association between ANGPTL4 and age-related metabolic disorders, as well as injury to renal tubular epithelial cells. This suggests that targeting ANGPTL4 could be a viable strategy for the clinical treatment of renal aging.

Cross-species analysis and comparison of the inner ear between chickens and mice.

The inner ear of mammals includes the cochlea and vestibule, which house specialized hair cells that are responsible for hearing and balance, respectively. While cochlear hair cells fail to regenerate following damage, those of the utricle, which is part of the vestibular apparatus, show partial regeneration. In birds, the macula lagena, a unique ear structure in this clade, has the ability to regenerate hair cells similarly to the utricle. Many studies have sought to explain regeneration in terms of evolution and species differences. However, it remains unclear what the cellular and molecular basis is behind the differences in inner ear structures and between avians and mammals. In the present study, we first investigated the anatomical structures of the inner ear of both chickens and rodents. We then performed RNA sequencing (RNA-Seq) and made cross-species analyses of the expression of homologous genes obtained from the inner ear tissue from both chickens and mice. Finally, we focused on the lagena, the basilar papilla, and the utricle in chickens and identified differentially expressed genes between tissues and determined the expression patterns of genes involved in inner ear structure formation by single-cell RNA sequencing and bulk RNA-Seq. We concluded that the cellular and molecular composition of the lagena is more similar to that of the utricle than the cochlea. Taken together, our study provides a valuable resource for the study of inner ear evolution and development.