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Coronavirus disease 19 (COVID-19) has occurred for more than four years, and the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causing COVID-19 is a strain of coronavirus, which presents high rates of morbidity around the world. Up to the present date, there are no therapeutics that can avert this form of illness, and photodynamic therapy (PDT) may be an alternative approach against SARS-CoV-2. Curcumin and methylene blue have been approved and used in clinical practices as a photosensitizer in PDT for a long time with their anti-viral properties and for disinfection through photo-inactivated SARS-CoV-2. Previously, curcumin and methylene blue with antibacterial properties have been used against Gram-positive bacteria, Staphylococcus aureus (S. aureus), and Gram-negative bacteria, Escherichia coli (E. coli), Enterococcus faecalis (E. faecalis), and Pseudomonas aeruginosa (P. aeruginosa). Methods: To conduct a literature review, nine electronic databases were researched, such as WanFang Data, PubMed, Science Direct, Scopus, Web of Science, Springer Link, SciFinder, and China National Knowledge Infrastructure (CNKI), without any regard to language constraints. In vitro and in vivo studies were included that evaluated the effect of PDT mediated via curcumin or methylene blue to combat bacteria and SARS-CoV-2. All eligible studies were analyzed and summarized in this review. Results: Curcumin and methylene blue inhibited the replication of SARS-CoV-2. The reactive oxygen species (ROS) are generated during the treatment of PDT with curcumin and methylene blue to prevent the attachment of SARS-CoV-2 on the ACE2 receptor and damage to the nucleic acids either DNA or RNA. It also modulates pro-inflammatory cytokines and attenuates the clotting effects of the host response. Conclusion: The photodynamic action of curcumin and methylene blue provides a possible approach against bacteria and SARS-CoV-2 infection because they act as non-toxic photosensitizers in PDT with an antibacterial effect, anti-viral properties, and disinfection functions. [ABSTRACT FROM AUTHOR]

Schisandrae Chinensis Fructus (SCF), the fruit of Schisandra chinensis (Turcz.) Baill. (family Schisandraceae) is traditionally used as a tonic and antidiabetic agent in Asia. In this study, SCF was investigated for its effects on sodium glucose cotransporters 1 and 2 (SGLT 1 and 2) expressed in a COS-7 cell line for its specificity in inhibiting SGLT2, which is a novel mechanism to screen for potential antidiabetic agents. Using a bioassay-guided fractionation, we then tried to isolate and identify the active fraction(s)/component(s). The ethanol extract of SCF at a concentration of 1 mg/mL significantly inhibited 89% of SGLT1 and 73% of SGLT2 activities in a [14C]-α-methyl-d-glucopyranoside ([14C]-AMG) uptake assay. Fractionation of the ethanol extract yielded nine fractions, of which F8, at a concentration of 1 mg/mL, was specific in inhibiting SGLT 2 (42% inhibition, P < 0.001), without inhibiting SGLT 1. Using LC/MS-MS, three compounds, deoxyschisandrin, schisandrin B (γ-schisandrin) and schisandrin were identified in F8 and their amounts quantified. However, subsequent evaluation in the [14C]-AMG uptake assay showed that these three compounds failed to inhibit SGLT 2 activity indicating that the SGLT active component(s) from SCF have yet to be identified. Drug [ABSTRACT FROM AUTHOR]

Background: Nasopharyngeal carcinoma (NPC) is one of the most common cancers, and exploring novel therapeutic modalities will improve the clinical outcomes. It has been confirmed that photodynamic therapy can efficiently deactivate malignant cells. The aim of the present study was to explore the photodynamic effects of pyropheophorbide-a methyl ester (MPPa) in CNE2 nasopharyngeal carcinoma cells., Material/methods: CNE2 cells were subjected to photodynamic therapy with MPPa, in which the drug concentration was 0.25 to 4 microM and light energy 1 to 8 J/cm(2). Photodynamic toxicity was investigated 24 h after treatment. Apoptosis was determined using flow cytometry with annexin V-FITC and propidum iodine staining and with nuclear staining with Hoechst 33258. The mitochondrial membrane potential (DeltaPsim) was evaluated by Rhodamine 123 assay., Results: There was no dark cytotoxicity of MPPa in the CNE2 cells at doses of 0.25-4 microM, and MPPa resulted in dose- and light-dependent phototoxicity. The apoptotic rate 8 h after PDT with MPPa (2 microM) increased to 16.43% under a light energy of 2 J/cm(2). Mitochondrial membrane potential (DeltaPsim) collapsed when the CNE2 cells were exposed to 2 microM MPPa for 20 h and then 2 J/cm(2) irradiation., Conclusions: Photodynamic therapy with MPPa significantly enhanced apoptosis and the collapse of DeltaPsim. This can be developed for treating nasopharyngeal carcinoma.