Dieckol isolated from Eisenia bicyclis extract suppresses RANKL-induced osteoclastogenesis in murine RAW 264.7 cells

Objective: To demonstrate the effect of dieckol from Eisenia bicyclis on osteoclastogenesis using RAW 264.7 cells. Methods: Murine macrophage RAW 264.7 cells were subjected to dieckol treatment, followed by treatment with receptor activator of nuclear factor kappa-B ligand (RANKL) to induce osteoclastogenesis. Tartrate-resistant acid phosphatase (TRAP) activity was examined using a TRAP activity kit. Western blotting analysis was conducted to examine the level of osteoclast- related factors, including TRAP and calcitonin receptor (CTR), transcriptional factors, including c-Fos, c-Jun, and nuclear factor of activated T cells cytoplasmic 1 (NFATc1), nuclear factor kappa-B (NF-κB), extracellular signal-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK). Immunofluorescence staining was conducted to examine the expression of c-Fos, c-Jun, and NFATc1. Results: Among the four phlorotannin compounds present in Eisenia bicyclis, dieckol significantly hindered osteoclast differentiation and expression of RANKL-induced TRAP and CTR. In addition, dieckol downregulated the expression levels of c-Fos, c-Jun, NFATc1, ERK, and JNK, and suppressed NF-κB signaling. Conclusions: Dieckol can suppress RANKL-induced osteoclastogenesis. Therefore, it has therapeutic potential in treating osteoclastogenesis- associated diseases.

Dieckol isolated from Eisenia bicyclis extract suppresses RANKL-induced osteoclastogenesis in murine RAW 264.7 cells

Objective: To demonstrate the effect of dieckol from Eisenia bicyclis on osteoclastogenesis using RAW 264.7 cells. Methods: Murine macrophage RAW 264.7 cells were subjected to dieckol treatment, followed by treatment with receptor activator of nuclear factor kappa-B ligand (RANKL) to induce osteoclastogenesis. Tartrate-resistant acid phosphatase (TRAP) activity was examined using a TRAP activity kit. Western blotting analysis was conducted to examine the level of osteoclast- related factors, including TRAP and calcitonin receptor (CTR), transcriptional factors, including c-Fos, c-Jun, and nuclear factor of activated T cells cytoplasmic 1 (NFATc1), nuclear factor kappa-B (NF-κB), extracellular signal-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK). Immunofluorescence staining was conducted to examine the expression of c-Fos, c-Jun, and NFATc1. Results: Among the four phlorotannin compounds present in Eisenia bicyclis, dieckol significantly hindered osteoclast differentiation and expression of RANKL-induced TRAP and CTR. In addition, dieckol downregulated the expression levels of c-Fos, c-Jun, NFATc1, ERK, and JNK, and suppressed NF-κB signaling. Conclusions: Dieckol can suppress RANKL-induced osteoclastogenesis. Therefore, it has therapeutic potential in treating osteoclastogenesis- associated diseases.

Different therapeutic associations of renin-angiotensin system inhibitors with coronavirus disease 2019 compared with usual pneumonia

Background/Aims@#Although it is near concluded that renin-angiotensin system inhibitors do not have a harmful effect on coronavirus disease 2019 (COVID-19), there is no report about whether angiotensin receptor blockers (ARBs) and angiotensin-converting enzyme inhibitors (ACEIs) offer any protective role. This study aimed to compare the association of ARBs and ACEIs with COVID-19-related mortality. @*Methods@#All patients with COVID-19 in Korea between January 19 and April 16, 2020 were enrolled. The association of ARBs and ACEIs with mortality within 60 days were evaluated. A comparison of hazard ratio (HR) was performed between COVID-19 patients and a retrospective cohort of pneumonia patients hospitalized in 2019 in Korea. @*Results@#Among 10,448 COVID-19 patients, ARBs and ACEIs were prescribed in 1,231 (11.7%) and 57 (0.6%) patients, respectively. After adjusting for age, sex, and history of comorbidities, the ARB group showed neutral association (HR, 1.034; 95% CI, 0.765 to 1.399; p = 0.8270) and the ACEI groups showed no significant associations likely owing to the small population size (HR, 0.736; 95% CI, 0.314 to 1.726; p = 0.4810). When comparing HR between COVID-19 patients and a retrospective cohort of patients hospitalized with pneumonia in 2019, the trend of ACEIs showed similar benefits, whereas the protective effect of ARBs observed in the retrospective cohort was absent in COVID-19 patients. Meta-analyses showed significant positive correlation with survival of ACEIs, whereas a neutral association between ARBs and mortality. @*Conclusions@#Although ARBs or ACEIs were not associated with fatal outcomes, potential beneficial effects of ARBs observed in pneumonia were attenuated in COVID-19.

Anti-senescence and anti-wrinkle activities of 3-bromo-4,5-dihydroxybenzaldehyde from Polysiphonia morrowii Harvey in human dermal fibroblasts

Objective:To investigate the anti-senescence effect of 3-bromo-4,5-dihydroxybenzaldehyde (BDB) from Polysiphonia morrowii Harvey in human dermal fibroblasts (HDF). Methods:HDF were subjected to treatment of BDB and then treated with hydrogen peroxide (H2O2) to induce premature senescence. Senescence-associated β-galactosidase (SA-β-gal) activity in HDF was determined using the SA-β-gal staining method. Intracellular reactive oxygen species (ROS) production was measured using the 2',7'-dichlorodihydrofluorescein diacetate assay. Western blotting assay was performed to assess the level of antioxidant enzyme glutathione peroxidase 1 (GPX1). In addition, intracellular collagen and collagenase contents were analyzed using the respective ELISA kits. Elastase activity in HDF supernatants was measured from p-nitroaniline release and normalized using total protein content. Results:Treatment of HDF with H2O2 increased the activity of SA-β-gal, but BDB pre-treatment resulted in the reduction of SA-β-gal activity. Moreover, BDB significantly reduced H2O2-induced intracellular ROS production. BDB also markedly increased the level of GPX1, which was inhibited by 400 μM of H2O2. Furthermore, in in vitro study, BDB significantly increased intracellular collagen content and decreased matrix metalloproteinase-1 and elastase activities in HDF. Conclusions:Our results demonstrate that BDB shows anti-senescence and anti-wrinkle activities in vitro.

Different therapeutic associations of renin-angiotensin system inhibitors with coronavirus disease 2019 compared with usual pneumonia

Background/Aims@#Although it is near concluded that renin-angiotensin system inhibitors do not have a harmful effect on coronavirus disease 2019 (COVID-19), there is no report about whether angiotensin receptor blockers (ARBs) and angiotensin-converting enzyme inhibitors (ACEIs) offer any protective role. This study aimed to compare the association of ARBs and ACEIs with COVID-19-related mortality. @*Methods@#All patients with COVID-19 in Korea between January 19 and April 16, 2020 were enrolled. The association of ARBs and ACEIs with mortality within 60 days were evaluated. A comparison of hazard ratio (HR) was performed between COVID-19 patients and a retrospective cohort of pneumonia patients hospitalized in 2019 in Korea. @*Results@#Among 10,448 COVID-19 patients, ARBs and ACEIs were prescribed in 1,231 (11.7%) and 57 (0.6%) patients, respectively. After adjusting for age, sex, and history of comorbidities, the ARB group showed neutral association (HR, 1.034; 95% CI, 0.765 to 1.399; p = 0.8270) and the ACEI groups showed no significant associations likely owing to the small population size (HR, 0.736; 95% CI, 0.314 to 1.726; p = 0.4810). When comparing HR between COVID-19 patients and a retrospective cohort of patients hospitalized with pneumonia in 2019, the trend of ACEIs showed similar benefits, whereas the protective effect of ARBs observed in the retrospective cohort was absent in COVID-19 patients. Meta-analyses showed significant positive correlation with survival of ACEIs, whereas a neutral association between ARBs and mortality. @*Conclusions@#Although ARBs or ACEIs were not associated with fatal outcomes, potential beneficial effects of ARBs observed in pneumonia were attenuated in COVID-19.

Antimicrobial activity of crude extracts prepared from fungal mycelia

Objective To evaluate the in vitro antimicrobial property of three different partitioned extracts (petroleum ether, ethanol and water) prepared from some fungal mycelia. Methods Seven fungal mycelia were prepared, initially extracted with acidified ethanol (0.2 mol/L HCl in 80% ethanol), yielding the raw crude extracts. The obtained extracts were then further partitioned with petroleum ether (F1), ethanol (F2) and water (F3). All the fractions were tested for antimicrobial activity using the disc diffusion assay. Results Our data showed that all the fractions could inhibit the testing bacteria. However, the inhibitory activity was found to be dependent on (i) the fungal strains used; (ii) the solvent extracted; and (iii) the testing bacteria assayed. In general, the ethanolic extracts (F2) derived from all fungi displayed highest inhibitory activity against the testing bacteria except for Chaetomium sp. Conclusions The findings of the present study concluded that the extracts prepared from the fungal mycelia had the bioactive compounds with antibacterial property. This study is a pioneering work and further study should be carried out for development of the new drug leads.