Suppression of angiotensin converting enzyme 2, a host receptor for SARS-CoV-2 infection, using 5-aminolevulinic acid in vitro.

Angiotensin converting enzyme 2 (ACE2), an entry receptor found on the surface of host cells, is believed to be detrimental to the infectious capability of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Scientists have been working on finding a cure since its outbreak with limited success. In this study, we evaluated the potential of 5-aminolevulinic acid hydrochloride (ALA) in suppressing ACE2 expression of host cells. ACE2 expression and the production of intracellular porphyrins following ALA administration were carried out. We observed the reduction of ACE2 expression and intracellular porphyrins following ALA administration. ALA suppressed the ACE2 expression in host cells which might prevent binding of SARS-CoV-2 to host cells. Co-administration of ALA and sodium ferrous citrate (SFC) resulted in a further decrease in ACE2 expression and increase in intracellular heme level. This suggests that the suppression of ACE2 expression by ALA might occur through heme production. We found that the inhibition of heme oxygenase-1 (HO-1), which is involved in heme degradation, also resulted in decrease in ACE2 expression, suggesting a potential role of HO-1 in suppressing ACE2 as well. In conclusion, we speculate that ALA, together with SFC administration, might serve as a potential therapeutic approach in reducing SARS-CoV-2 infectivity through suppression of ACE2 expression.

Association of SARS-CoV-2 RNA Copy Number with the COVID-19 Mortality Rate and Its Effect on the Predictive Performance of Mortality in Severe Cases.

Factors associated with mortality are important in the treatment of coronavirus disease 2019 (COVID-19). Polymerase chain reaction (PCR) is the gold standard for diagnosing COVID-19, which reflects the viral load in the upper respiratory tract. In total, 523 patients were enrolled in this study; of them, 441 and 75 patients underwent PCR testing of nasopharyngeal swabs and sputum samples, respectively, within 20 days from onset of COVID-19. We investigated the association between RNA copy number and the COVID-19 severity and mortality rate and its effect on the predictive performance for severity and mortality. RNA copy numbers in nasopharyngeal swabs were higher in the non-survivor group than in the survivor group. Multivariate logistic regression analysis identified that the high RNA copy number (≥9 log10 /swab) in nasopharyngeal swabs was a factor associated with mortality (odds ratio, 4.50; 95% confidence interval, 1.510-13.100; P = 0.008). Furthermore, adding RNA copy number (≥9 log10 /swab) in severe cases, adjusted by duration from onset to PCR, improved mortality predictive performance based on known factors. The RNA copy number is a factor associated with the mortality of patients with COVID-19 and can improve the predictive performance of mortality in severe cases.

An Experience of Multiple Hematomas in a Coronavirus Disease-19 Patient Administered with ART-123 and Heparin.

BACKGROUND: Anticoagulant therapy for patients with severe coronavirus disease (COVID-19) pneumonia is considered to improve the hypercoagulable and inflammatory state. However, bleeding complications should also be considered. CASE PRESENTATION: A 77-year-old man with a history of falls was diagnosed with COVID-19. Owing to his severe condition, he was intubated and transferred to our hospital for intensive care. Favipiravir, tocilizumab, unfractionated heparin, and ART-123 were administered to treat COVID-19 and manage the antithrombotic prophylaxis for paroxysmal atrial fibrillation (Af). On the 6th day after admission, a hematoma was noted on the left chest wall. Computed tomography (CT) revealed multiple hematomas, including hematomas on his chest wall and obturatorius internus muscle. Emergency angiography transcatheter embolization (TAE) was performed. The patient was transferred to another hospital 23 days after TAE, without complications. CONCLUSION: Our findings show that anticoagulation therapy and a history of falls induced multiple hematomas in a COVID-19 patient and that the condition was managed with TAE. When anticoagulants are considered in the management of Af and COVID-19 associated coagulopathy, it is necessary to closely monitor potential bleeding complications.

Predictors associated with clinical improvement of SARS-CoV-2 pneumonia.

BACKGROUND: There are few agents that have been proven effective for COVID-19. Predicting clinical improvement as well as mortality or severity is very important. OBJECTIVES: This study aimed to investigate the factors associated with the clinical improvement of COVID-19. METHODS: Overall, 74 patients receiving treatment for COVID-19 at Tokyo Medical and Dental University Hospital from April 6th to May 15th, 2020 were included in this study. Clinical improvement was evaluated, which defined as the decline of two levels on a six-point ordinal scale of clinical status or discharge alive from the hospital within 28 days after admission. The clinical courses were particularly investigated and the factors related to time to clinical improvement were analyzed with the log-rank test and the Cox proportional hazard model. RESULTS: Forty-nine patients required oxygen support during hospitalization, 22 patients required invasive mechanical ventilation, and 5 patients required extracorporeal membrane oxygenation. A total of 83% of cases reached clinical improvement. Longer period of time from onset to admission (≥10 days) (HR, 1.057; 95% CI, 1.002-1.114), no hypertension (HR, 2.077; 95% CI, 1.006-4.287), and low D-dimer levels (<1 µg/ml) (HR, 2.372; 95% CI, 1.229-4.576) were confirmed to be significant predictive factors for time to clinical improvement. Furthermore, a lower SARS-CoV-2 RNA copy number was also a predictive factor for clinical improvement. CONCLUSIONS: Several predictors for the clinical improvement of COVID-19 pneumonia were identified. These results may be important for the management of COVID-19 pneumonia.

MuLBSTA score is a useful tool for predicting COVID-19 disease behavior.

BACKGROUND: The prediction of COVID-19 disease behavior in the early phase of infection is challenging but urgently needed. MuLBSTA score is a scoring system that predicts the mortality of viral pneumonia induced by a variety of viruses, including coronavirus, but the scoring system has not been verified in novel coronavirus pneumonia. The aim of this study was to validate this scoring system for estimating the risk of disease worsening in patients with COVID-19. METHODS: This study included the patients who were treated between April 1 st and March 13 th , 2020. The patients were classified into mild, moderate, and severe groups according to the extent of respiratory failure. MuLBSTA score was applied to estimate the risk of disease worsening in each severity group and we validated the utility of the scoring system. RESULTS: A total of 72 patients were analyzed. Among the 46 patients with mild disease, 17 showed disease progression to moderate or severe disease after admission. The model showed a sensitivity of 100% and a specificity of only 34.5% with a cut-off value of 5 points. Among the 55 patients with mild or moderate disease, 6 deteriorated to severe disease, and the model showed a sensitivity of 83.3% and a specificity of 71.4% with a cut-off value of 11 points. CONCLUSIONS: This study showed that MuLBSTA score is a potentially useful tool for predicting COVID-19 disease behavior. This scoring system may be used as one of the criteria to identify high-risk patients worsening to life-threatening status.