Since the role of the liver in metabolic dysfunction, including type 2 diabetes mellitus, was demonstrated, studies on non-alcoholic fatty liver disease (NAFLD) and metabolic dysfunction-associated fatty liver disease (MAFLD) have shown associations between fatty liver disease and other metabolic diseases. Unlike the exclusionary diagnostic criteria of NAFLD, MAFLD diagnosis is based on the presence of metabolic dysregulation in fatty liver disease. Renaming NAFLD as MAFLD also introduced simpler diagnostic criteria. In 2023, a new nomenclature, steatotic liver disease (SLD), was proposed. Similar to MAFLD, SLD diagnosis is based on the presence of hepatic steatosis with at least one cardiometabolic dysfunction. SLD is categorized into metabolic dysfunction-associated steatotic liver disease (MASLD), metabolic dysfunction and alcohol-related/-associated liver disease, alcoholrelated liver disease, specific etiology SLD, and cryptogenic SLD. The term MASLD has been adopted by a number of leading national and international societies due to its concise diagnostic criteria, exclusion of other concomitant liver diseases, and lack of stigmatizing terms. This article reviews the diagnostic criteria, clinical relevance, and differences among NAFLD, MAFLD, and MASLD from a diabetologist’s perspective and provides a rationale for adopting SLD/MASLD in the Fatty Liver Research Group of the Korean Diabetes Association.

Since the role of the liver in metabolic dysfunction, including type 2 diabetes mellitus, was demonstrated, studies on non-alcoholic fatty liver disease (NAFLD) and metabolic dysfunction-associated fatty liver disease (MAFLD) have shown associations between fatty liver disease and other metabolic diseases. Unlike the exclusionary diagnostic criteria of NAFLD, MAFLD diagnosis is based on the presence of metabolic dysregulation in fatty liver disease. Renaming NAFLD as MAFLD also introduced simpler diagnostic criteria. In 2023, a new nomenclature, steatotic liver disease (SLD), was proposed. Similar to MAFLD, SLD diagnosis is based on the presence of hepatic steatosis with at least one cardiometabolic dysfunction. SLD is categorized into metabolic dysfunction-associated steatotic liver disease (MASLD), metabolic dysfunction and alcohol-related/-associated liver disease, alcoholrelated liver disease, specific etiology SLD, and cryptogenic SLD. The term MASLD has been adopted by a number of leading national and international societies due to its concise diagnostic criteria, exclusion of other concomitant liver diseases, and lack of stigmatizing terms. This article reviews the diagnostic criteria, clinical relevance, and differences among NAFLD, MAFLD, and MASLD from a diabetologist’s perspective and provides a rationale for adopting SLD/MASLD in the Fatty Liver Research Group of the Korean Diabetes Association.

Since the role of the liver in metabolic dysfunction, including type 2 diabetes mellitus, was demonstrated, studies on non-alcoholic fatty liver disease (NAFLD) and metabolic dysfunction-associated fatty liver disease (MAFLD) have shown associations between fatty liver disease and other metabolic diseases. Unlike the exclusionary diagnostic criteria of NAFLD, MAFLD diagnosis is based on the presence of metabolic dysregulation in fatty liver disease. Renaming NAFLD as MAFLD also introduced simpler diagnostic criteria. In 2023, a new nomenclature, steatotic liver disease (SLD), was proposed. Similar to MAFLD, SLD diagnosis is based on the presence of hepatic steatosis with at least one cardiometabolic dysfunction. SLD is categorized into metabolic dysfunction-associated steatotic liver disease (MASLD), metabolic dysfunction and alcohol-related/-associated liver disease, alcoholrelated liver disease, specific etiology SLD, and cryptogenic SLD. The term MASLD has been adopted by a number of leading national and international societies due to its concise diagnostic criteria, exclusion of other concomitant liver diseases, and lack of stigmatizing terms. This article reviews the diagnostic criteria, clinical relevance, and differences among NAFLD, MAFLD, and MASLD from a diabetologist’s perspective and provides a rationale for adopting SLD/MASLD in the Fatty Liver Research Group of the Korean Diabetes Association.

Since the role of the liver in metabolic dysfunction, including type 2 diabetes mellitus, was demonstrated, studies on non-alcoholic fatty liver disease (NAFLD) and metabolic dysfunction-associated fatty liver disease (MAFLD) have shown associations between fatty liver disease and other metabolic diseases. Unlike the exclusionary diagnostic criteria of NAFLD, MAFLD diagnosis is based on the presence of metabolic dysregulation in fatty liver disease. Renaming NAFLD as MAFLD also introduced simpler diagnostic criteria. In 2023, a new nomenclature, steatotic liver disease (SLD), was proposed. Similar to MAFLD, SLD diagnosis is based on the presence of hepatic steatosis with at least one cardiometabolic dysfunction. SLD is categorized into metabolic dysfunction-associated steatotic liver disease (MASLD), metabolic dysfunction and alcohol-related/-associated liver disease, alcoholrelated liver disease, specific etiology SLD, and cryptogenic SLD. The term MASLD has been adopted by a number of leading national and international societies due to its concise diagnostic criteria, exclusion of other concomitant liver diseases, and lack of stigmatizing terms. This article reviews the diagnostic criteria, clinical relevance, and differences among NAFLD, MAFLD, and MASLD from a diabetologist’s perspective and provides a rationale for adopting SLD/MASLD in the Fatty Liver Research Group of the Korean Diabetes Association.

Aromadendrin is a phenolic compound with various biological effects such as anti-inflammatory properties. However, its protective effects against acute lung injury (ALI) remain unclear. Therefore, this study aimed to explore the ameliorative effects of aromadendrin in an experimental model of lipopolysaccharide (LPS)-induced ALI. In vitro analysis revealed a notable increase in the levels of cytokine/chemokine formation, nuclear factor kappa B (NF-κB) activation, and myeloid differentiation primary response 88 (MyD88)/toll-like receptor (TLR4) expression in LPS-stimulated BEAS-2B lung epithelial cell lines that was ameliorated by aromadendrin pretreatment. In LPS-induced ALI mice, the remarkable upregulation of immune cells and IL-1β/IL-6/TNF-α levels in the bronchoalveolar lavage fluid and inducible nitric oxide synthase/cyclooxygenase-2/CD68 expression in lung was decreased by the oral administration of aromadendrin. Histological analysis revealed the presence of cells in the lungs of ALI mice, which was alleviated by aromadendrin. In addition, aromadendrin ameliorated lung edema. This in vivo effect of aromadendrin was accompanied by its inhibitory effect on LPS-induced NF-κB activation, MyD88/TLR4 expression, and signal transducer and activator of transcription 3 activation. Furthermore, aromadendrin increased the expression of heme oxygenase-1/ NAD(P)H quinone dehydrogenase 1 in the lungs of ALI mice. In summary, the in vitro and in vivo studies demonstrated that aromadendrin ameliorated endotoxin-induced pulmonary inflammation by suppressing cytokine formation and NF-κB activation, suggesting that aromadendrin could be a useful adjuvant in the treatment of ALI.

Chronic respiratory diseases such as idiopathic pulmonary fibrosis, chronic obstructive pulmonary disease, and respiratory infections injure the alveoli; the damage evoked is mostly irreversible and occasionally leads to death. Achieving a detailed understanding of the pathogenesis of these fatal respiratory diseases has been hampered by limited access to human alveolar tissue and the differences between mice and humans. Thus, the development of human alveolar organoid (AO) models that mimic in vivo physiology and pathophysiology has gained tremendous attention over the last decade. In recent years, human pluripotent stem cells (hPSCs) have been successfully employed to generate several types of organoids representing different respiratory compartments, including alveolar regions. However, despite continued advances in three-dimensional culture techniques and single-cell genomics, there is still a profound need to improve the cellular heterogeneity and maturity of AOs to recapitulate the key histological and functional features of in vivo alveolar tissue. In particular, the incorporation of immune cells such as macrophages into hPSC-AO systems is crucial for disease modeling and subsequent drug screening. In this review, we summarize current methods for differentiating alveolar epithelial cells from hPSCs followed by AO generation and their applications in disease modeling, drug testing, and toxicity evaluation. In addition, we review how current hPSC-AOs closely resemble in vivo alveoli in terms of phenotype, cellular heterogeneity, and maturity.

Background: The value of tiotropium bromide (TIO) in neutrophilic asthma was meaningful in previous study. We hypothesized that TIO’s mechanism of action is associated with histone deacetylase 2 (HDAC2) activity, which is key for controlling the transcription of inflammatory cytokines and usually downregulated in neutrophilic asthma. Methods: The effects of TIO and dexamethasone (DEX) on HDAC2 activity, nuclear factor kappa B (NF-κB), and C-X-C motif chemokine ligand 1 (CXCL1) were evaluated in neutrophilic asthma mouse model (C57BL, 6-week-old). An in-vitro study was conducted using primary human bronchial/tracheal epithelial (HBE) cells from asthma patients.Western blot analyses were performed for phospho-phospholipase Cγ-1 (PLCγ-1) and inositol trisphosphate (IP3 ) receptors (IP3 R) with treating lipopolysaccharide (LPS) and TIO. Results: Ovalbumin was used to induce eosinophilic inflammation in this study. After neutrophilic asthma was induced by LPS (O+L group), HDAC2 activity was diminished with increased NF-κB activity and CXCL1 compared to the control group. TIO significantly improved NF-κB activity, CXCL1, and HDAC2 activity compared with the O+L group in in-vivo study (P < 0.05, each). Western blot analyses showed that LPS treated HBE cells from asthma patients increased PLCγ-1 and diminished IP3 receptor levels. After TIO treatment, recovery of IP3 R and improved PLCγ-1 levels were observed. Conclusion These results support the hypothesis that TIO modulates inflammation by recovering HDAC2 activity from the acetylcholine-stimulated inflammation cascade in neutrophilic asthma. The detailed inflammation cascade of recovering HDAC2 activity by TIO might be associated with PLCγ-1-IP3-IP3R mediated intracellular calcium ion pathway.

Background: The Global Initiative for Chronic Obstructive Lung Disease (GOLD) update 2023 proposed new definitions of chronic obstructive pulmonary disease (COPD) and COPD exacerbation. However, an agreement on the definitions has not been made, either internationally or domestically. This study aimed to reach an agreement between experts on the new definitions of COPD and COPD exacerbation in South Korea. Methods: A modified Delphi method was used to make an agreement on the definitions of COPD and COPD exacerbation proposed by the GOLD update 2023. We performed two rounds of the survey including 15 Korean experts on COPD, asthma, and tuberculosis. Results: More than two-thirds of the experts agreed on 12 of the 13 statements related to the definitions of COPD and COPD exacerbation in the two rounds of the survey. The experts agreed on the definitions of COPD and COPD exacerbation that should be revised in line with the definitions proposed by the GOLD update 2023. However, the experts showed an uncertain opinion on the statement that the definition of COPD includes patients with persistent airflow obstruction due to bronchiectasis. Conclusion Based on this Delphi survey, experts’ agreement was made on the definitions of COPD and COPD exacerbation proposed by the GOLD update 2023.

Background: Numerous patients around the globe are dying from coronavirus disease 2019 (COVID-19). While age is a known risk factor, risk analysis in the young generation is lacking. The present study aimed to evaluate the clinical features and mortality risk factors in younger patients (≤ 50 years) with a critical case of COVID-19 in comparison with those among older patients (> 50 years) in Korea. Methods: We analyzed the data of adult patients only in critical condition (requiring high flow nasal cannula oxygen therapy or higher respiratory support) hospitalized with PCR-confirmed COVID-19 at 11 hospitals in Korea from July 1, 2021 to November 30, 2021 when the delta variant was a dominant strain. Patients’ electronic medical records were reviewed to identify clinical characteristics. Results: During the study period, 448 patients were enrolled. One hundred and forty-two were aged 50 years or younger (the younger group), while 306 were above 50 years of age (the older group). The most common pre-existing conditions in the younger group were diabetes mellitus and hypertension, and 69.7% of the patients had a body mass index (BMI) > 25 kg/m 2 .Of 142 younger patients, 31 of 142 patients (21.8%, 19 women) did not have these pre-existing conditions. The overall case fatality rate among severity cases was 21.0%, and it differed according to age: 5.6% (n = 8/142) in the younger group, 28.1% in the older group, and 38% in the ≥ 65 years group. Age (odds ratio [OR], 7.902; 95% confidence interval [CI], 2.754–18.181), mechanical ventilation therapy (OR, 17.233; 95% CI, 8.439–35.192), highest creatinine > 1.5 mg/dL (OR, 17.631; 95% CI, 8.321–37.357), and combined blood stream infection (OR, 7.092;95% CI, 1.061–18.181) were identified as independent predictors of mortality in total patients.Similar patterns were observed in age-specific analyses, but most results were statistically insignificant in multivariate analysis due to the low number of deaths in the younger group.The full vaccination rate was very low among study population (13.6%), and only three patients were fully vaccinated, with none of the patients who died having been fully vaccinated in the younger group. Seven of eight patients who died had a pre-existing condition or were obese (BMI > 25 kg/m 2 ), and the one remaining patient died from a secondary infection. Conclusion About 22% of the patients in the young critical group did not have an underlying disease or obesity, but the rate of obesity (BMI > 25 kg/m2 ) was high, with a fatality rate of 5.6%. The full vaccination rate was extremely low compared to the general population of the same age group, showing that non-vaccination has a grave impact on the progression of COVID-19 to a critical condition. The findings of this study highlight the need for measures to prevent critical progression of COVID-19, such as vaccinations and targeting young adults especially having risk factors.

Background: Because the etiologies of bronchiectasis and related diseases vary significantly among different regions and ethnicities, this study aimed to develop a diagnostic bundle for bronchiectasis in South Korea. Methods: A modified Delphi method was used to develop expert consensus statements on a diagnostic bundle for bronchiectasis in South Korea. Initial statements proposed by a core panel, based on international bronchiectasis guidelines, were discussed in an online meeting and two email surveys by a panel of experts (≥70% agreement). Results: The study involved 21 expert participants, and 30 statements regarding a diagnostic bundle for bronchiectasis were classified as recommended, conditional, or not recommended. The consensus statements of the expert panel were as follows: A standardized diagnostic bundle is useful in clinical practice; diagnostic tests for specific diseases, including immunodeficiency and allergic bronchopulmonary aspergillosis, are necessary when clinically suspected; initial diagnostic tests, including sputum microbiology and spirometry, are essential in all patients with bronchiectasis, and patients suspected with rare causes such as primary ciliary dyskinesia should be referred to specialized centers. Conclusion Based on this Delphi survey, expert consensus statements were generated including specific diagnostic, laboratory, microbiological, and pulmonary function tests required to manage patients with bronchiectasis in South Korea.