Methoxylated Flavones from Casimiroa edulis La Llave Suppress MMP9 Expression via Inhibition of the JAK/STAT3 Pathway and TNFα-Dependent Pathways.

Matrix metalloproteinase 9 (MMP9), an MMP isozyme, plays a crucial role in tumor progression by degrading basement membranes. It has therefore been proposed that the pharmacological inhibition of MMP9 expression or activity could inhibit tumor metastasis. We previously isolated two novel methoxylated flavones, casedulones A and B, from the leaves and/or roots of Casimiroa edulis La Llave and determined that these casedulones have antitumor activity that acts via the reduction of MMP9. Here, we examined how these casedulones suppress lipopolysaccharide (LPS)-induced MMP9 expression in human monocytic THP-1 cells. The casedulones suppressed the LPS-induced signal transducer and activator of transcription 3 (STAT3) pathway, which participates in MMP9 induction. In addition, AG490 and S3I-201, inhibitors of Janus kinase (JAK) and STAT3, suppressed LPS-mediated MMP9 induction, suggesting that the casedulones suppressed MMP9 induction through the inhibition of JAK/STAT3 pathways. Based on the findings that cycloheximide, an inhibitor of de novo protein synthesis, completely inhibited LPS-mediated MMP9 induction, the role of de novo proteins in MMP9 induction was further investigated. We found that the casedulones inhibited the induction of interleukin-6 (IL-6), a key inflammatory cytokine that participates in STAT3 activation. Moreover, tumor necrosis factor-α (TNFα)-mediated MMP9 induction was significantly suppressed in the presence of the casedulones. Taken together, these findings suggest that casedulones inhibit the IL-6/STAT3 and TNFα pathways, which all involve LPS-mediated MMP9 induction.

The inciting factor for bradycardia in COVID-19 patients: a potential harm of steroid treatment.

Background: The coronavirus disease 2019 (COVID-19) is a condition caused by the novel severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2). Although several papers have reported the presence bradycardia in patients with COVID-19, the pathophysiology behind this remains unclear. Therefore, we investigated the presence of bradycardia in patients with COVID-19. Methods: We conducted a retrospective cohort study in a total of 153 patients with COVID-19 and 90 patients with influenza who were hospitalized in our hospital from January 1, 2020 to December 31, 2021 and from January 1, 2014 to December 31, 2021, respectively. Data were collected from patient medical records, which included sex, age, duration of hospitalization, pneumonia complications, supplemental oxygen therapy, antiviral treatment, past history, and vital signs. Results: After adjustment, the incidence of bradycardia and steroid use in patients with COVID-19 were significantly higher than those in patients with influenza (P=0.007 and P<0.001, respectively). We then compared the detailed characteristics of patients with COVID-19 to evaluate risk factors for bradycardia. Multivariate logistic regression analysis revealed that steroid use was significantly related to bradycardia [P=0.031; odds ratio (OR): 3.67; 95% confidence interval (CI): 1.12-11.96]. Overall, results showed a higher incidence of bradycardia in patients with COVID-19 who received steroid treatment. Conclusions: Our results showed that steroid treatment in patients with COVID-19 may be associated with the incidence of bradycardia.

The epidemiology of pulmonary Mycobacterium abscessus species in Japanese population.

BACKGROUND: Mycobacterium abscessus species (MABS) is now a most virulent rapidly growing mycobacteria (RGM), and the rapid increase of MABS was recently observed worldwide, including in Japan. Thus, we gathered evidences of the presence of pulmonary MABS in Japanese population from Japanese articles. METHODS: we searched studies that addressed the isolation of pulmonary non-tuberculous Mycobacteria (NTM) or MABS from clinical respiratory specimens in Japan. RESULTS: the ratio of MABS to NTM was 3.04% (95% confidence interval [CI]: 2.51-3.68), found using the meta-analysis of single proportions. The estimated mean age of patients infected with MABS was 67.72 years (95% CI: 65.41-70.02), found using the meta-analysis of single means. The estimated proportion of females, never smoker, and the co-infection with Mycobacterium avium complex (MAC) was 66.75% (95% CI: 59.23-73.50), 67.57% (95% CI: 62.43-72.32), and 36.74% (95% CI: 25.30-49.90), respectively. The characteristics of MABS in Japan were considerably different from that in Europe and United States from the perspective of age, gender, and complications, wherein the patients in these countries tended to be younger, had lower number of females, and had more occurrences of hereditary diseases, including cystic fibrosis (CF). CONCLUSION: we hypothesized that the characteristics of MABS in the Japanese were involved in those of non-CF MABS, and the distribution of gender and age of MABS were similar to that of MAC in the Japanese.

Two new methoxylated flavones isolated from Casimiroa edulis La Llave and their MMP-9 inhibitory activity.

Casimiroa edulis La Llave is known to contain unusual 5,6-dimethoxyflavones bearing a variously oxygenated B-ring. Phytochemical investigation of the leaves and the roots of C. edulis achieved the isolation of two new methoxylated flavones, named casedulones A (1) and B (2), together with 12 known analogues. Their unique structures were established with the aid of spectral analyses and total syntheses. Pre-treatment with 20 µM of 1 and 2 suppressed MMP-9 expression in LPS-mediated THP-1 cells, indicating that the characteristic flavonoids in C. edulis could be potential anti-angiogenics for cancer prevention.

Morphological change of skin fibroblasts induced by UV Irradiation is involved in photoaging.

Human dermal fibroblasts (HDFs) are typically flattened or extensible shaped and play a critical role in the metabolism of extracellular matrix components. As the properties of fibroblasts in the dermis are considered to be influenced by their morphology, we investigated the morphological changes induced in fibroblasts by ultraviolet (UV) irradiation as well as the relationship between these changes and collagen metabolism. In this study, we showed that UVA exposure induced morphological changes and reduced collagen contents in HDFs. These morphological changes were accompanied a reduction in actin filaments and upregulation of the actin filament polymerization inhibitor, capping protein muscle Z-line ɑ1 (CAPZA1). External actin filament growth inhibitors also affected the shape of HDFs and reduced collagen levels. These results suggest that UVA exposure may inhibit the polymerization of actin filaments and induce morphological changes in skin fibroblasts. These morphological changes in fibroblasts may accelerate reductions in collagen synthesis. This mechanism may be one of the processes responsible for collagen reductions observed in photoaged skin. When natural materials that suppress these morphological changes in HDFs were evaluated, we found that an extract of Lilium 'Casa Blanca' (LCB) suppressed UVA-induced alterations in the shape of HDFs, which are typically followed by inhibition of collagen reduction. An analysis of the active compounds in LCB extract led to the identification of regaloside I, which had a structure of phenylpropanoid glycerol glucoside, as the active compound inhibiting the upregulation of CAPZA1. Therefore, inhibition of UVA-induced morphological changes in HDFs is considered to be promising way for the suppression of collagen reduction in photoaging.