Hydroxychloroquine in COVID-19 Therapy: Protection Versus Proarrhythmia

Organoid technology and lung injury mouse models evaluating effects of hydroxychloroquine on lung epithelial regeneration

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) damages lung epithelial stem/progenitor cells. Ideal anti-SARS-CoV-2 drug candidates should be screened to prevent secondary injury to the lungs. Here, we propose that in vitro three-dimensional organoid and lung injury repair mouse models are powerful models for the screening antiviral drugs. Lung epithelial progenitor cells, including airway club cells and alveolar type 2 (AT2) cells, were co-cultured with supportive fibroblast cells in transwell inserts. The organoid model was used to evaluate the possible effects of hydroxychloroquine, which is administered as a symptomatic therapy to COVID-19 patients, on the function of mouse lung stem/progenitor cells. Hydroxychloroquine was observed to promote the self-renewal of club cells and differentiation of ciliated and goblet cells in vitro. Additionally, it inhibited the self-renewal ability of AT2 cells in vitro. Naphthalene- or bleomycin-induced lung injury repair mouse models were used to investigate the in vivo effects of hydroxychloroquine on the regeneration of club and AT2 cells, respectively. The naphthalene model indicated that the proliferative ability and differentiation potential of club cells were unaffected in the presence of hydroxychloroquine. The bleomycin model suggested that hydroxychloroquine had a limited effect on the proliferation and differentiation abilities of AT2 cells. These findings suggest that hydroxychloroquine has limited effects on the regenerative ability of epithelial stem/progenitor cells. Thus, stem/progenitor cell-derived organoid technology and lung epithelial injury repair mouse models provide a powerful platform for drug screening, which could possibly help end the pandemic.

Combining hydroxychloroquine and minocycline: potential role in moderate to severe COVID-19 infection

INTRODUCTION

Patients with moderate to severe COVID-19 infection require specific drugs to prevent the morbidity and mortality. Hydroxychloroquine (HCQ) has shown some promise in the management of COVID 19. Minocycline, because of its anticytokine and other useful properties can be an ideal candidate for combining with HCQ.

AREAS COVERED

Here we review the need and mechanisms and reasons for combining HCQ and minocycline moderate to severe COVID-19 infection. We also reviewed the advantages, potential safety concerns and precautions to be taken, while combining HCQ and minocycline.

EXPERT OPINION

Combining HCQ and minocycline offers many advantages in the management of moderate to severe COVID-19 infection. Both drugs are cheaper, widely available and long-term safety data and contraindications are well known. We do not recommend this combination for prophylaxis or use in asymptomatic or mild disease patients as this can lead to unnecessary safety concerns. Additive antimicrobial and anticytokine effects of both drugs may reduce the morbidity and mortality among patients with COVID-19 and may act as a cheaper alternative to the costlier drugs, however, thorough clinical research is warranted. We call upon public and private healthcare bodies to come up with large well-designed clinical studies for generating evidence-based recommendations.