Zinc and respiratory tract infections: Perspectives for COVID‑19

forrás: https://www.spandidos-publications.com/ijmm/46/1/17


2021-01-22 09:50:43


In view of the emerging COVID‑19 pandemic caused by SARS‑CoV‑2 virus, the search for potential protective and therapeutic antiviral strategies is of particular and urgent interest. Zinc is known to modulate antiviral and antibacterial immunity and regulate inflammatory response. Despite the lack of clinical data, certain indications suggest that modulation of zinc status may be beneficial in COVID‑19. In vitro experiments demonstrate that Zn2+ possesses antiviral activity through inhibition of SARS‑CoV RNA polymerase. This effect may underlie therapeutic efficiency of chloroquine known to act as zinc ionophore. Indirect evidence also indicates that Zn2+ may decrease the activity of angiotensin‑converting enzyme 2 (ACE2), known to be the receptor for SARS‑CoV‑2. Improved antiviral immunity by zinc may also occur through up‑regulation of interferon α production and increasing its antiviral activity. Zinc possesses anti‑inflammatory activity by inhibiting NF‑κB signaling and modulation of regulatory T‑cell functions that may limit the cytokine storm in COVID‑19. Improved Zn status may also reduce the risk of bacterial co‑infection by improving mucociliary clearance and barrier function of the respiratory epithelium, as well as direct antibacterial effects against S. pneumoniae. Zinc status is also tightly associated with risk factors for severe COVID‑19 including ageing, immune deficiency, obesity, diabetes, and atherosclerosis, since these are known risk groups for zinc deficiency. Therefore, Zn may possess protective effect as preventive and adjuvant therapy of COVID‑19 through reducing inflammation, improvement of mucociliary clearance, prevention of ventilator‑induced lung injury, modulation of antiviral and antibacterial immunity. However, further clinical and experimental studies are required.

 


Computational screening of antagonists against the SARS-CoV-2 (COVID-19) coronavirus by molecular docking

forrás: http://medpublics.com/docs/computational_screening.pdf


2021-01-21 14:14:58


In the current spread of novel coronavirus (SARS-CoV-2), antiviral drug discovery is of great importance. AutoDock Vina was used to screen potential drugs by molecular docking with the structural protein and non-structural protein sites of new coronavirus. Ribavirin, a common antiviral drug, remdesivir, chloroquine and luteolin were studied. Honeysuckle is generally believed to have antiviral effects in traditional Chinese medicine. In this study, luteolin (the main flavonoid in honeysuckle) was found to bind with a high affinity to the same sites of the main protease of SARS-CoV-2 as the control molecule. Chloroquine has been proved clinically effective and can bind to the main protease; this may be the antiviral mechanism of this drug. The study was restricted to molecular docking without validation by molecular dynamics simulations. Interactions with the main protease may play a key role in fighting against viruses. Luteolin is a potential antiviral molecule worthy of attention

 


COVID-19: CHLOROQUINE, ZINC AND QUERCETIN

forrás: https://dadamo.com/dangerous/2020/04/07/covid-19-chloroquine-zinc-and-quercetin/


2021-01-06 10:31:28


Chloroquine is a malarial drug first discovered in 1934. It’s still in use for malaria management, although the most common species of malaria-causing organisms are long resistant to it. Hydroxychloroquine (Plaquenil) also has anti-malarial activity, but is much more commonly used to treat certain auto-immune disorders, including rheumatoid arthritis, and systemic lupus erythematosus. Both of these drugs are structurally related to quinine, the famous ‘Jesuit Bark’ (Chinchona spp.) that was the first effective treatment for malaria (and the chemical that gives tonic water its unique flavor). Both pharmaceuticals are long out of patent protection, so generic versions are widely available. Depending on locale, a typical month-long treatment with hydroxychloroquine in the developing world was about US $4.65. Both drugs are on the World Health Organization’s List of Essential Medicines.

All quinine-analog drugs have the potential for side effects. Some are mild (diarrhea, nausea, tinnitus) others can be quite serious (inflammation of the retina, anemia, cardiac instability). Chloroquine and hydroxychloroquine preferentially collect in the lungs, which helps increase potency with smaller doses. However, part of risk is due to the medications also collecting more in cells with melanin, which include skin and eye cells. Damage to the eyes can be a risk with large doses or extended use as a malaria or autoimmune disease treatment. People with cardiac problems may also be more at risk of adverse cardiac reactions. There is also a significant risk of interactions with other medications when taken simultaneously. Because of this, both chloroquine and hydroxychloroquine are available only by prescription.

Chloroquine and hydroxychloroquine have an extensive research basis as antivirals. There are two acknowledged mechanisms by which these drugs exert antiviral effects.


A Sars-CoV-2 (COVID-19) koronavírussal szembeni antagonisták számítógépes szűrése molekuláris dokkolással

forrás: http://medpublics.com/docs/computational_screening.pdf


2021-01-21 14:14:58


Az új koronavírus (SARS-CoV-2) jelenlegi terjedése mellett nagy fontossága van egy vírusellenes gyógyszer felfedezésének. A potenciális gyógyszerek szűrésére az AutoDock Vina-t használták az új koronavírus strukturális fehérje és nem-strukturális fehérje helyeinek molekuláris dokkolásával. A ribavirint, ami egy általános vírusellenes gyógyszer, a remdesivirt, a klorokvint és a luteolint vizsgálták. A loncról általában úgy vélik a hagyományos kínai orvoslásban, hogy vírusellenes hatásai vannak. Ebben a kutatásban a luteolinról (amely a lonc fő flavonoidja), hogy magas affinitással kötődik a SARS-CoV-2 fő proteázának ugyanazon helyeihez, mint a kontroll molekula. A klorokvinról bebizonyosodott, hogy klinikailag hatásos és képes a fő proteázhoz kötődni; ez lehet ennek a gyógyszernek a vírusellenes mechanizmusa. Ez a kutatás a molekuláris dokkolásra korlátozódott, és nem lett validálva molekuláris dinamikai szimulációkkal. A kölcsönhatások a fő proteázzal kulcsszerepet játszhatnak a vírusok elleni küzdelemben. A luteolin egy figyelemre méltó potenciális vírusellenes molekula.

 


COVID-19: KLOROKVIN, CINK ÉS KVERCETIN

forrás: https://dadamo.com/dangerous/2020/04/07/covid-19-chloroquine-zinc-and-quercetin/


2021-01-06 10:31:28


A klorokvin egy maláriaellenes gyógyszer, amelyet először 1934-ben fedeztek fel. Még mindig használják a malária kezelésére, bár a maláriát okozó organizmusok leggyakoribb fajtái már régen rezisztensek vele szemben. A hidroxiklorokvinnak (Plaquenil) is van maláriaellenes hatása, bár sokkal inkább használják bizonyos autoimmun rendellenességek, köztük a reumatoid artritiszt és a szisztémás lupus erythematosus (LSE) kezelésére. Strukturálisan mindkét gyógyszer a kininhez, a híres „jezsuita kéreghez” (Chinchona spp.) kapcsolódik, amely a malária első hatásos kezelése volt (és ez az a kémiai anyag, amely a tonik egyedülálló ízét adja). A két gyógyszer már régóta nem áll szabadalmi oltalom alatt, így generikus változataik széles körben hozzáférhetőek. A helytől függően egy átlagos, egy hónapig tartó hidroxiklorokvinnal történő kezelés egy havi költsége a fejlődő világban körülbelül US $ 4,65 körül van. Mindkét gyógyszer fenn van az Egészségügyi Világszervezet Alapvető Gyógyszerek listáján.


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