Investigation of the mechanism of silica-induced pulmonary fibrosis: The role of lung microbiota dysbiosis and the LPS/TLR4 signaling pathway

The widespread manufacture of silica and its extensive use, and potential release of silica into the environment pose a serious human health hazard. Silicosis, a severe global public health issue, is caused by exposure to silica, leading to persistent inflammation and fibrosis of the lungs. The underlying pathogenic mechanisms of silicosis remain elusive. Lung microbiota dysbiosis is associated with the development of inflammation and fibrosis. However, limited information is currently available regarding the role of lung microbiota in silicosis. The study therefore is designed to conduct a comprehensive analysis of the role of lung microbiota dysbiosis and establish a basis for future investigations into the potential mechanisms underlying silicosis. Here, the pathological and biochemical parameters were used to systematically assessed the degree of inflammation and fibrosis following silica exposure and treatment with combined antibiotics. The underlying mechanisms were studied via integrative multi-omics analyses of the transcriptome and microbiome. Analysis of 16S ribosomal DNA revealed dysbiosis of the microbial community in silicosis, characterized by a predominance of gram-negative bacteria. Exposure to silica has been shown to trigger lung inflammation and fibrosis, leading to an increased concentration of lipopolysaccharides in the bronchoalveolar lavage fluid. Furthermore, Toll-like receptor 4 was identified as a key molecule in the lung microbiota dysbiosis associated with silica-induced lung fibrosis. All of these outcomes can be partially controlled through combined antibiotic administration. The study findings demonstrate that the dysbiosis of lung microbiota enhances silica-induced fibrosis associated with the lipopolysaccharides/Toll-like receptor 4 pathway and provided a promising target for therapeutic intervention of silicosis.

MiR-148a-3p within HucMSC-Derived Extracellular Vesicles Suppresses Hsp90b1 to Prevent Fibroblast Collagen Synthesis and Secretion in Silica-Induced Pulmonary Fibrosis

Silicosis is a fatal occupational respiratory disease caused by the prolonged inhalation of respirable silica. The core event of silicosis is the heightened activity of fibroblasts, which excessively synthesize extracellular matrix (ECM) proteins. Our previous studies have highlighted that human umbilical cord mesenchymal stem cell-derived extracellular vesicles (hucMSC-EVs) hold promise in mitigating silicosis and the significant role played by microRNAs (miRNAs) in this process. Delving deeper into this mechanism, we found that miR-148a-3p was the most abundant miRNA of the differential miRNAs in hucMSC-EVs, with the gene heat shock protein 90 beta family member 1 (Hsp90b1) as a potential target. Notably, miR-148a-3p's expression was downregulated during the progression of silica-induced pulmonary fibrosis both in vitro and in vivo, but was restored after hucMSC-EVs treatment (p < 0.05). Introducing miR-148a-3p mimics effectively hindered the collagen synthesis and secretion of fibroblasts induced by transforming growth factor-β1 (TGF-β1) (p < 0.05). Confirming our hypothesis, Hsp90b1 was indeed targeted by miR-148a-3p, with significantly reduced collagen activity in TGF-β1-treated fibroblasts upon Hsp90b1 inhibition (p < 0.05). Collectively, our findings provide compelling evidence that links miR-148a-3p present in hucMSC-EVs with the amelioration of silicosis, suggesting its therapeutic potential by specifically targeting Hsp90b1, thereby inhibiting fibroblast collagen activities. This study sheds light on the role of miR-148a-3p in hucMSC-EVs, opening avenues for innovative therapeutic interventions targeting molecular pathways in pulmonary fibrosis.

[Analysis of clinical characteristics of middle ear osteoma at different locations]

Objective: To explore the clinical characteristics, intervention and treatment of tympanic osteoma at different locations. Methods: The medical history, audiological and imaging examination, operation and follow-up results of two patients with tympanic osteoma at different sites were reviewed and summarized. Furthermore, the clinical characteristics and interventions of 36 patients reported in literatures with tympanic osteomas were also summarized and analyzed. Results: Osteoma of the two patients collected in this study located at promontory and incus respectively;both of them presented with intact tympanum and conductive deafness, without obvious etiology or predisposing factor. Both of them underwent surgeries and the hearing improved significantly. For patient one, the ossicular chain was intact and restored to activity after removed the osteoma. For patient two, an artificial ossicle was implanted after removed the osteoma and incus. In the 36 patients reported in literatures, the average age was 26.5 years, and 39.47% of them located at promontory; in addition, the main symptoms of them were progressive hearing loss, tinnitus and ear stuffy. Conclusions: Patients with tympanic osteoma are characterized by conduction deafness with intact tympanic membrane, and the most common lesion is promontory. Hearing can be restored by excision of the osteoma and maintenance or reconstruction of the ossicle chain.

miR-200b promotes cell proliferation and invasion in t-cell acute Lymphoblastic leukemia through NOTCH1

MicroRNA-200b (miR-200b) functions as an oncogenic regulator in human lung cancer. However, the effect of miRNA-200b on the development and progression of T-Cell acute lymphoblastic leukemia (T-ALL) remains largely unknown. In this study, we evaluated the impact of miR-200b in T-ALL cell proliferation, survival and invasion using gain and loss of function approaches. Human Jurkat cells, a widely used in-vitro T-ALL cell model, were transfected with miR-200b mimic or miR-200b inhibitor. miR-200b mimics substantially inhibited Jurkat cell proliferation and invasion while significantly stimulating cell apoptosis compared to the control miRNA-treated cells. In contrast, Jurkat cells treated with anti-miR200 demonstrated induction of cell growth and invasion but repression of cell apoptosis. Such effect was accompanied by the corresponding alteration in NOTCH1 expression, suggesting that NOTCH1 might be the target gene for miR-200b function in Jurkat cells. In summary, our findings demonstrate that miR-200b may serve as a potential therapeutic target for T-ALL by negatively regulating the NOTCH1 signaling pathway.

Associations between birth size and later height from infancy through adulthood: An individual based pooled analysis of 28 twin cohorts participating in the CODATwins project

BACKGROUND

There is evidence that birth size is positively associated with height in later life, but it remains unclear whether this is explained by genetic factors or the intrauterine environment.

AIM

To analyze the associations of birth weight, length and ponderal index with height from infancy through adulthood within mono- and dizygotic twin pairs, which provides insights into the role of genetic and environmental individual-specific factors.

METHODS

This study is based on the data from 28 twin cohorts in 17 countries. The pooled data included 41,852 complete twin pairs (55% monozygotic and 45% same-sex dizygotic) with information on birth weight and a total of 112,409 paired height measurements at ages ranging from 1 to 69 years. Birth length was available for 19,881 complete twin pairs, with a total of 72,692 paired height measurements. The association between birth size and later height was analyzed at both the individual and within-pair level by linear regression analyses.

RESULTS

Within twin pairs, regression coefficients showed that a 1-kg increase in birth weight and a 1-cm increase in birth length were associated with 1.14-4.25 cm and 0.18-0.90 cm taller height, respectively. The magnitude of the associations was generally greater within dizygotic than within monozygotic twin pairs, and this difference between zygosities was more pronounced for birth length.

CONCLUSION

Both genetic and individual-specific environmental factors play a role in the association between birth size and later height from infancy to adulthood, with a larger role for genetics in the association with birth length than with birth weight.

Calcium-dependent Nedd4-2 upregulation mediates degradation of the cardiac sodium channel Nav1.5: implications for heart failure

AIM

Reductions in voltage-gated sodium channel (Nav1.5) function/expression provide a slowed-conduction substrate for cardiac arrhythmias. Nedd4-2, which is activated by calcium, post-translationally modulates Nav1.5. We aim to investigate whether elevated intracellular calcium ([Ca²⁺ ]_i ) reduces Nav1.5 through Nedd4-2 and its role in heart failure (HF).

METHODS

Using a combination of biochemical, electrophysiological, cellular and in vivo methods, we tested the effect and mechanism of calcium on Nedd4-2 and in turn Nav1.5.

RESULTS

Increased [Ca²⁺ ]_i , following 24-h ionomycin treatment, decreased sodium current (I_Na ) density and Nav1.5 protein without altering its mRNA in both neonatal rat cardiomyocytes (NRCMs) and HEK 293 cells stably expressing Nav1.5. The calcium chelator BAPTA-AM restored the reduced Nav1.5 and I_Na in NRCMs pre-treated by ionomycin. Nav1.5 was decreased by Nedd4-2 transfection and further decreased by 6-h ionomycin treatment. These effects were not observed in cells transfected with the catalytically inactive mutant, Nedd4-2 C801S, or with Y1977A-Nav1.5 mutant containing the impaired Nedd4-2 binding motif. Furthermore, elevated [Ca²⁺ ]_i increased Nedd4-2, the interaction between Nedd4-2 and Nav1.5, and Nav1.5 ubiquitination. Nav1.5 protein is decreased, whereas Nedd4-2 is increased in volume-overload HF rat hearts, with increased co-localization of Nav1.5 with ubiquitin or Nedd4-2 as indicated by immunofluorescence staining. BAPTA-AM rescued the reduced Nav1.5 protein, I_Na and increased Nedd4-2 in hypertrophied NRCMs induced by isoproterenol or angiotensin II.

CONCLUSION

Calcium-mediated increases in Nedd4-2 downregulate Nav1.5 by ubiquitination. Nav1.5 is downregulated and co-localizes with Nedd4-2 and ubiquitin in failing rat heart. These data suggest a role of Nedd4-2 in Nav1.5 downregulation in HF.

Exposure to famine in early life and the risk of obesity in adulthood in Qingdao: Evidence from the 1959-1961 Chinese famine

BACKGROUND AND AIMS

We aimed to evaluate the association between famine exposure during early life and obesity and obesity_max (obese at the highest weight) in adulthood.

METHODS AND RESULTS

Data were from two population-based cross-sectional surveys conducted in 2006 and 2009 in Qingdao, China. A total of 8185 subjects born between 1/1/1941 and 12/31/1971 were categorized into unexposed (born between 01/01/1962 and 12/31/1971), fetal/infant exposed (born between 01/01/1959 and 12/31/1961), childhood exposed (born between 01/01/1949 and 12/31/1958) and adolescence exposed (born between 01/01/1941 and 12/31/1948) according to their age when exposed to the Chinese famine from 1959 to 1961. Obesity was defined as BMI (body mass index) ≥28.0 and obesity_max was defined as BMI_max (BMI at the highest weight) ≥28.0. We compared fetal/infant exposed, childhood exposed and adolescence exposed to the unexposed using logistic regression models to assess the effect of famine exposure on later obesity and obesity_max. Fetal/infant exposed (OR = 1.59, P < 0.001), childhood exposed (OR = 1.42, P < 0.01) and adolescence exposed (OR = 1.86, P < 0.01) all had higher risks of obesity than the unexposed. Exposure groups were more likely to be obese at their highest weight than the unexposed, and ORs (95%CIs) for obesity_max in the fetal/infant exposed, childhood exposed and adolescence exposed were 1.49(1.20-1.86), 1.24(1.02-1.49) and 1.64 (1.40-1.93), respectively. Similar results were found in both men and women.

CONCLUSION

Exposure to famine in early life was associated with increased risks of obesity and obesity_max in adulthood. Preventing undernutrition in early life appears beneficial to reduce the prevalence of later obesity.

Cardiovascular risk profiles in relation to newly diagnosed type 2 diabetes diagnosed by either glucose or HbA1c criteria in Chinese adults in Qingdao, China

AIMS

To study the cardiovascular disease risk profiles in newly diagnosed diabetes diagnosed by either glucose or/and HbA(1c) criteria in Chinese adults.

METHODS

Two population-based cross-sectional studies were conducted in 2006 and 2009, respectively. Data from 1987 men and 2815 women aged 35-74 years were analysed. Newly diagnosed diabetes was defined according to either glucose (fasting and/or 2-h glucose), HbA(1c) or both criteria.

RESULTS

Ageing, positive family history of diabetes, elevated levels of waist circumference, systolic blood pressure, total cholesterol, triglycerides and γ-glutamyl transferase were independently associated with newly diagnosed diabetes defined by glucose criterion alone, but not for diabetes defined by HbA(1c) criterion alone. Only waist circumference, total cholesterol and smoking were significantly associated with the presence of diabetes defined by HbA(1c) criterion alone.

CONCLUSIONS

Cardiovascular disease risk profiles were different in patients with newly diagnosed diabetes defined by the two diagnostic criteria for diabetes. This may have certain clinical implications on diabetes management and research.

Diabetes self-risk assessment questionnaires coupled with a multimedia health promotion campaign are cheap and effective tools to increase public awareness of diabetes in a large Chinese population

AIMS

To evaluate costs and effectiveness of implementing a diabetes self-risk assessment (Diabetes Risk Score) questionnaire coupled with a multimedia health promotion campaign on changes in diabetes awareness in a large diabetes prevention programme.

METHODS

Between 2007 and 2010, a multimedia health promotion campaign was conducted targeting the 1.94 million population of Qingdao, China, using newspapers, radio programmes, distribution of free booklets and Diabetes Risk Score flyers. Diabetes awareness questionnaires filled out by people first interviewed in 2006 (survey A), before the initiation of the campaign, were compared with those first interviewed between 2007 and 2010 during the campaign period (survey B). The rates of diabetes awareness in both surveys were studied amongst adults aged 35-74 years without a prior history of diabetes, but with a Diabetes Risk Score of ≥ 14.

RESULTS

In survey B, 85, 82 and 76% of the urban participants correctly recognized obesity, family history of diabetes and physical inactivity, respectively, as important risk factors for diabetes; while the awareness rates were 43, 46 and 25%, respectively, in survey A (P < 0.001). The corresponding figures among rural participants were 65, 63 and 53% in survey B and 29, 22 and 11% in survey A (P < 0.001). To cover 1000 individuals, the programme spent €5.4 on the use of the Diabetes Risk Score flyer, €31.3 on the education booklet, €7.7 on the newspaper campaign and €37.5 on radio programmes.

CONCLUSIONS

The combination of a Diabetes Risk Score questionnaire with a multimedia health promotion campaign is a cheap and effective health promotion tool to raise public awareness of diabetes.

Prevalence of metabolic syndrome in rural and urban Chinese population in Qingdao

AIMS

To investigate the prevalence of metabolic syndrome and its components in both rural and urban Chinese population.

SUBJECTS AND METHODS

A population-based crosssectional survey was conducted in Qingdao, China in 2006 with 6100 Chinese aged 35-74 yr invited and 5355 who attended; 3357 subjects, 1562 urban (46.5%) and 1795 rural residents (53.5%) met the inclusion criteria for the current data analysis. The metabolic syndrome definitions of National Cholesterol Education Program Adult Treatment Expert Panel III (NCEPATPIII) 2004, NCEP 2005 and International Diabetes Federation (IDF) were used.

RESULTS

The age-standardized prevalences of metabolic syndrome were 16.2%, 32.2%, and 28.3% in men and 26.8%, 37.2%, and 34.6%in women, according to the definitions of the NCEP 2004, NCEP 2005, and IDF, respectively. Urban men have more risk factors and higher prevalence of the metabolic syndrome than rural men, but the differences in women were not that striking. Elevated blood pressure (62.6%) was, among risk factors, most common in the study population, followed by central obesity (53.4%), and hyperglycemia (52.2%) defined using the NCEP 2005 criteria.

CONCLUSIONS

Metabolic disorders were common among adult Chinese in both rural and urban areas in Qingdao.

Does abnormal insulin action or insulin secretion explain the increase in prevalence of impaired glucose metabolism with age in populations of different ethnicities?

BACKGROUND

Age is associated with both impaired glucose and insulin metabolism. To what extent the age-related changes in insulin resistance (IR) and beta-cell function contribute to the increase in prevalence of impaired fasting glucose (IFG) and impaired glucose tolerance (IGT) is less known, and this is investigated in this study.

METHODS

This study included 6610 men and 7664 women of different ethnic groups aged 30-69 years. IR and beta-cell function were examined by the homeostasis model assessment of insulin resistance (HOMA-IR) and homeostasis model assessment of beta-cell function (HOMA-B). Odds ratios (ORs) and 95% confidence intervals (95% CIs) were estimated using logistic regression analysis adjusting for body mass index and study.

RESULTS

In Chinese men, the ORs (95% CIs) for IFG were 2.69 (1.70, 4.26), 2.51 (1.49, 4.21) and 2.89 (1.68, 4.97), respectively, in age groups of 40-49, 50-59 and 60-69 years compared with 30-39 years (p < 0.001 for trend); the corresponding figures for IGT were 1.73 (1.25, 2.38), 2.54 (1.78, 3.63) and 3.57 (2.46, 5.19) (p < 0.001 for trend). Similar trends for IGT were observed also in Chinese women and other ethnic groups, but not for IFG in Mauritius Indian and Creole men. Adjustment for HOMA-IR and HOMA-B reduced the ORs in all age groups of all ethnicities for both IFG and IGT, but the risk gradient between age groups remained particularly for the IGT.

CONCLUSIONS

The age-related increase in glucose intolerance may not be fully explained by the defect in HOMA-IR and HOMA-B. As HOMA-IR and HOMA-B are only surrogate measures of insulin sensitivity and insulin secretion, the results need to be further investigated.

Increasing trend in the prevalence of Type 2 diabetes and pre-diabetes in the Chinese rural and urban population in Qingdao, China

AIMS

To determine the secular trend of prevalence of Type 2 diabetes and pre-diabetes in a Chinese population from 2001 to 2006.

METHODS

Two consecutive population-based surveys for diabetes were conducted in a randomly selected population aged 35-74 years and living in Qingdao, China in 2001-2002 (n = 10854) and 2006 (n = 4416). All participants underwent standardized 2-h 75-g oral glucose tolerance tests (OGTTs), along with fasting capillary plasma glucose (FCG) tests in 2006. One urban community underwent OGTTs directly in 2002 (n = 1815), while a two-step screening strategy using FCG as a first-line screening test followed by OGTTs was used in 9039 individuals in 2001. Diabetes and pre-diabetes was defined according to the 2006 World Health Organization/International Diabetes Federation criteria.

RESULTS

Based on the results of direct OGTTs, the age-standardized prevalence of diabetes and pre-diabetes in urban areas was 12.2 and 15.4% in 2002, whereas the prevalences were 18.8 and 28.7% in urban areas and 14.1 and 20.2% in rural areas in 2006 (P < 0.001, in urban areas). Using the two-step screening strategy, the prevalence of diabetes in 2001 was 10.1% in urban and 7.7% in rural areas and 13.8% in urban and 12.2% in rural areas in 2006 (P < 0.001). Based on the data of the 2006 survey, the two-step screening strategy missed 30.2% of diabetes cases when compared with the number defined by the direct OGTT approach.

CONCLUSIONS

Qingdao has experienced a marked increase in the prevalence of diabetes and pre-diabetes in the past 5 years. Intervention to prevent a further increase in the prevalence of diabetes is urgently required.

Risk factors associated with the dramatic increase in the prevalence of diabetes in the adult Chinese population in Qingdao, China

OBJECTIVE

To investigate the major risk factors and their association with the dramatic increase in the prevalence of diabetes from 2001-2002 to 2006 in Qingdao, China.

METHODS

Population-based cross-sectional studies on diabetes were performed in 4598 men and 7026 women aged 35-74 years. The 2006 World Health Organization diagnostic criteria for diabetes were used.

RESULTS

The crude prevalence of diabetes was 11.3% in both men and women in urban areas and 5.3% and 8.9% in rural areas in 2001-2002. This increased to 19.2% and 16.1% in urban areas and 14.2% and 13.8% in rural areas in 2006 for men and women, respectively. The increase in diabetes prevalence from 2001-2002 to 2006 was paralleled by an increased body mass index in rural areas but not in urban areas. The major risk factors associated with diabetes were age, family history of diabetes, obesity, hypertension and high triglycerides. The multivariate adjusted odds ratio and 95% confidence interval for diabetes corresponding to a one standard deviation increase in waist circumference was 1.81 (1.47, 2.23) in urban men, 1.64 (1.26, 2.13) in rural men, 1.98 (1.66, 2.37) in urban women and 2.02 (1.63, 2.51) in rural women. Low socio-economic classes had a higher risk for diabetes in urban areas but a lower risk in rural areas, both associated with increased waist circumference.

CONCLUSION

Established risk factors are of great importance for the prevalence of diabetes in the urban and rural Chinese populations and changes in these factors could explain the recent dramatic increase in diabetes prevalence, particularly in rural areas. Considering the high prevalence of obesity and physical inactivity, intervention is urgently required in China.

[Arterialization of the great saphenous vein for treating severe ischemia of lower limbs]

This study was to observe the result in patients suffering from severe ischemia of legs with arterialization of the great saphenous vein. Eighty nine patients suffering from the disease were treated by bridging the autogenous cephalic vein or Gore-Tex artificial vessel between the great saphenous vein and the femoral or external iliac arteries. The results showed that the blood supply of the affected legs was increased immediately after operation. The ulcers of the toes and the plantar areas were healed gradually and the pain relieved. It was concluded that this method did not interfere with the reflux of the venous blood in the diseased limbs. This method was simple, safe and effective for treating severe ischemia of the lower limbs.