Oxidative stress and selenoprotein deficiency are thought to be associated with the pathogenesis of Keshan disease (KD). However, to our knowledge, the level of oxidative stress and expression of selenoproteins have not been investigated in the myocardium of patients with KD. In this study, 8-hydroxy-2-deoxy guanosine (8-OH-dG), a marker of oxidative stress, was used to assess the level of oxidative stress, and thioredoxin reductase 1 (TrxR1) and glutathione peroxidase 1 (GPx1) were assessed to reflect the level of selenoproteins. Myocardial samples from 8 patients with KD and 9 non-KD patients (controls) were immunohistochemically stained for 8-OH-dG, TrxR1, and GPx1. The staining intensities were subsequently quantified using Olympus Image-Pro Plus 6.0 software. The data showed that the positive rate of 8-OH-dG expression in myocardial nuclei was higher in the KD group (68.6%) than that in the control group (2.4%). In addition, a positive correlation between the positive rate of 8-OH-dG and the degree of myocardial damage was observed in the KD group. The distribution of TrxR1 and GPx-1 was not associated with the distribution of myocardial damage. The expression of these two selenoproteins was higher in the control group than that in the KD group. Our study represents the first report on the expression profiles of oxidative stress and selenoproteins in the myocardium of patients with KD. The level of oxidative stress significantly increased and was positively correlated with the degree of myocardial damage in patients with KD. The selenoproteins, TrxR1 and GPx1, may have a role in the pathogenesis of KD.

What is already known about this topic? Kashin-Beck disease (KBD) is a chronic and degenerative osteoarthropathy characterized by cartilage degeneration. It is an endemic disease that is highly prevalent among the Chinese population and poses a significant health risk. What is added by this report? This is the first national report on the economic burden of KBD in China. According to the data from 2021, KBD has caused significant disease and economic burdens. The most substantial reduction in healthy life expectancy was observed among patients with degree II severity and those aged 60 years and older, resulting in a total indirect economic burden of 112.74 million Chinese Yuan (CNY). What are the implications for public health practice? The results of this study will contribute to informing the development of tailored prevention and control strategies by the government. These strategies will include targeted policies and recommendations for appropriate healthcare and financial subsidies, which will be based on the demographic characteristics of the endemic areas.

What is already known about this topic? Endemic fluorosis, caused by high fluoride levels in drinking water, has been a significant health issue in rural areas of China for many decades. What is added by this report? There has been a notable decline in the detection rate of dental fluorosis in children aged 8–12 years in drinking water fluorosis areas across the country from 2009 to 2022. While 14 provincial-level administrative divisions are classified as low-probability clusters, Tianjin remains classified as a high-probability cluster. What are the implications for public health practice? The current policy for preventing and controlling endemic fluorosis in China needs adjustment. Rather than focusing solely on regions with high incidence, there should be a shift towards monitoring and early warning of fluoride exposure. Additionally, local containment measures should be intensified.