Effectiveness of Drug Repurposing and Natural Products Against SARS-CoV-2: A Comprehensive Review.

The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is a betacoronavirus responsible for the COVID-19 pandemic, causing respiratory disorders, and even death in some individuals, if not appropriately treated in time. To face the pandemic, preventive measures have been taken against contagions and the application of vaccines to prevent severe disease and death cases. For the COVID-19 treatment, antiviral, antiparasitic, anticoagulant and other drugs have been reused due to limited specific medicaments for the disease. Drug repurposing is an emerging strategy with therapies that have already tested safe in humans. One promising alternative for systematic experimental screening of a vast pool of compounds is computational drug repurposing (in silico assay). Using these tools, new uses for approved drugs such as chloroquine, hydroxychloroquine, ivermectin, zidovudine, ribavirin, lamivudine, remdesivir, lopinavir and tenofovir/emtricitabine have been conducted, showing effectiveness in vitro and in silico against SARS-CoV-2 and some of these, also in clinical trials. Additionally, therapeutic options have been sought in natural products (terpenoids, alkaloids, saponins and phenolics) with promising in vitro and in silico results for use in COVID-19 disease. Among these, the most studied are resveratrol, quercetin, hesperidin, curcumin, myricetin and betulinic acid, which were proposed as SARS-CoV-2 inhibitors. Among the drugs reused to control the SARS-CoV2, better results have been observed for remdesivir in hospitalized patients and outpatients. Regarding natural products, resveratrol, curcumin, and quercetin have demonstrated in vitro antiviral activity against SARS-CoV-2 and in vivo, a nebulized formulation has demonstrated to alleviate the respiratory symptoms of COVID-19. This review shows the evidence of drug repurposing efficacy and the potential use of natural products as a treatment for COVID-19. For this, a search was carried out in PubMed, SciELO and ScienceDirect databases for articles about drugs approved or under study and natural compounds recognized for their antiviral activity against SARS-CoV-2.

Sloanea chocoana and S. pittieriana (Elaeocarpaceae): Chemical and Biological Studies of Ethanolic Extracts and Skincare Properties.

The Colombian Chocó is known for its rich biodiversity and to harbor plant species that are under-explored, including the genus Sloanea. This study aimed to analyze the chemical composition of derivatized ethanolic extracts from S. chocoana and S. pittieriana using BSTFA and TMCS through GC-MS, and to assess cell viability of immortalized human non-tumorigenic keratinocytes (HaCaT) and periodontal ligament fibroblast cells using crude extracts through MTS assay. Antioxidant and photoprotective properties were determined using DPPH assay and spectrophotometry. Antifungal activity of extracts against Candida species was developed following the CLSI standard M27, 4th ed. The sun protective factor (SPF) and UVA/UVB ratio values were calculated using the Mansur equation and the Boots star rating system. The critical wavelength (λc) was determined by calculating the integrated optical density curve's area. The transmission of erythema and pigmentation was calculated through equations that use constants to calculate the flux of erythema and pigmentation. The GC-MS analysis identified 37 compounds for S. chocoana and 38 for S. pittieriana, including alkaloids, triterpenoids, and polyphenolics, among others. Both extracts exhibited proliferative effects on periodontal ligament fibroblasts, did not affect the viability of HaCaT cells, and showed excellent antioxidant activities (46.1% and 43.7%). Relevant antifungal activity was observed with S. pittieriana extract against Candida albicans (GM-MIC: 4 µg/mL), followed by C. auris and C. glabrata (GM-MIC: 32 µg/mL), while S. chocoana extract was active against C. albicans and C. glabrata (GM-MIC: 16 and 32 µg/mL, respectively). High SPF values (31.0 and 30.0), λc (393.98 and 337.81 nm), UVA/UVB ratio (1.5 and 1.2), and low percentage of transmission of erythema and pigmentation were determined for S. chocoana and S. pittieriana, respectively. Results showed that species of Sloanea constitute a promising alternative as ingredients for developing skincare products, and exhaustive studies are required for their sustainable uses.

In vitro antiviral activity against SARS-CoV-2 of plant extracts used in Colombian traditional medicine / Actividad antiviral in vitro contra el SARS-CoV-2 de extractos de plantas usados en medicina tradicional colombiana

Background: Coronavirus infectious disease 2019 (COVID-19) caused by the infection with the new coronavirus SARS-CoV-2 has affected the life and health of more than 222 million people. In the absence of any specific pharmacological treatment, the need to find new therapeutic alternatives is clear. Medicinal plants are widely used worldwide to treat different conditions, including COVID-19; however, in most cases, there are no specific studies to evaluate the efficacy of these treatments. Objective: This article evaluates the antiviral effect of six plant extracts used by indigenous and afro Colombian people against SARS-CoV-2 in vitro. Methods: The antiviral effect of six extracts prepared from plants used in Colombian traditional medicine was evaluated against SARS-CoV-2 through a pre-post treatment strategy on the Vero E6 cell line. Once cytotoxicity was established through an MTT assay, the antiviral effect of the extracts was calculated based on the reduction in the viral titer determined by plaque assay. Results:Gliricidia sepium inhibited SARS-CoV-2 in a 75.6%, 56.8%, 62.5% and 40.0% at 10 mg/mL, 8 mg/mL, 6 mg/mL, and 2 mg/mL, respectively, while Piper tuberculatumtreatment reduced viral titer in 33.3% at 6 mg/mL after 48h. Conclusion:G. sepium and P. tuberculatum extracts exhibit antiviral activity against SARS-CoV-2 in vitro

Introducción: La enfermedad infecciosa causada por el coronavirus 2019 (COVID-19) generada por la infección con el nuevo coronavirus SARS-CoV-2 ha afectado la vida y la salud de mas de 222 millones de personas. En ausencia de algún tratamiento farmacológico específico, la necesidad de encontrar nuevas alternativas terapéuticas es clara. Las plantas medicinales son utilizadas en todo el mundo para tratar diferentes condiciones, incluyendo el COVID-19; sin embargo, en la mayoría de los casos no existen estudios específicos que evalúen la eficacia de estos tratamientos. Objetivo: En este artículo, evaluamos el efecto antiviral de seis extractos de plantas usadas por pueblos indígenas y afrocolombianos contra el SARS-CoV-2 in vitro.Metodología: El efecto antiviral de seis extractos preparados a partir de plantas usadas en medicina tradicional colombiana fue evaluado contra SARS-CoV-2 por medio de una estrategia de pre-post tratamiento en células Vero E6. Una vez se estableció la citotoxicidad por un ensayo de MTT, el efecto antiviral de estos extractos fue calculado basado en la reducción del título viral determinado por ensayo de plaqueo. Resultados:G. sepium inhibió SARS-CoV-2 en un 75.6%, 56.8%, 62.5% y 40.0% a 10 mg/mL, 8 mg/mL, 6 mg/mL, and 2 mg/mL, respectivamente. Mientras el extracto de Piper tuberculatum redujo el título viral en un 33.3% a 6 mg/mL luego de 48h de tratamiento

Natural Products with Inhibitory Activity against Human Immunodeficiency Virus Type 1.

Infections caused by human immunodeficiency virus (HIV) are considered one of the main public health problems worldwide. Antiretroviral therapy (ART) is the current modality of treatment for HIV-1 infection. It comprises the combined use of several drugs and can decrease the viral load and increase the CD4+ T cell count in patients with HIV-1 infection, thereby proving to be an effective modality. This therapy significantly decreases the rate of morbidity and mortality owing to acquired immunodeficiency syndrome (AIDS) and prolongs and improves the quality of life of infected patients. However, nonadherence to ART may increase viral resistance to antiretroviral drugs and transmission of drug-resistant strains of HIV. Therefore, it is necessary to continue research for compounds with anti-HIV-1 activity, exhibiting a potential for the development of an alternative or complementary therapy to ART with low cost and fewer side effects. Natural products and their derivatives represent an excellent option owing to their therapeutic potential against HIV. Currently, the derivatives of natural products available as anti-HIV-1 agents include zidovudine, an arabinonucleoside derivative of the Caribbean marine sponge (Tectitethya crypta), which inhibits the reverse transcriptase of the virus. This was the first antiviral agent approved for treatment of HIV infection. Additionally, bevirimat (isolated from Syzygium claviflorum) and calanolide A (isolated from Calophyllum sp.) are inhibitors of viral maturation and reverse transcription process, respectively. In the present review, we aimed to describe the wide repertoire of natural compounds exhibiting anti-HIV-1 activity that can be considered for designing new therapeutic strategies to curb the HIV pandemic.

Pentacyclic Triterpene Profile and Its Biosynthetic Pathway in Cecropia telenitida as a Prospective Dietary Supplement.

Promising research over the past decades has shown that some types of pentacyclic triterpenes (PTs) are associated with the prevention of type 2 diabetes (T2D), especially those found in foods. The most abundant edible sources of PTs are those belonging to the ursane and oleanane scaffold. The principal finding is that Cecropia telenitida contains abundant oleanane and ursane PT types with similar oxygenation patterns to those found in food matrices. We studied the compositional profile of a rich PT fraction (DE16-R) and carried out a viability test over different cell lines. The biosynthetic pathway connected to the isolated PTs in C. telenitida offers a specific medicinal benefit related to the modulation of T2D. This current study suggests that this plant can assemble isobaric, positional isomers or epimeric PT. Ursane or oleanane scaffolds with the same oxygenation pattern are always shared by the PTs in C. telenitida, as demonstrated by its biosynthetic pathway. Local communities have long used this plant in traditional medicine, and humans have consumed ursane and oleanane PTs in fruits since ancient times, two key points we believe useful in considering the medicinal benefits of C. telenitida and explaining how a group of molecules sharing a closely related scaffold can express effectiveness.

Pharmacological developments obtained from marine natural products and current pipeline perspective.

Marine organisms represent a new extensive source for bioactive molecules. They have the potential to provide new therapeutic alternatives to treat human diseases. In this paper, we describe and discuss a variety of isolated and semisynthetic molecules obtained from marine sources. These compounds are in phase II, phase III and at the commercialization stage of new drug development. A description of the mechanism of action, dosage used and side effects are also reported. The positive results obtained from these studies have triggered the development of new studies to evaluate the prospects for utilization of marine organisms.

Valores de referencia para el control de calidad de plantas medicinales como materia prima para fines terapéuticos en Colombia / Reference values for quality control of medicinal plants as raw materials for therapeutic purposes in Colombia

Se presentan los valores obtenidos, en el proceso de evaluación y desarrollo de métodos, para el control de calidad de 11 de las plantas medicinales aprobadas en Colombia: Semillas de anís (Pimpinella anisum), bulbos de ajo (Allium sativum), corteza de canela (Cinnamomum zeylanicum.), semillas de cardamomo (Elettaria cardamomum), flores de caléndula (Calendula officinalis), raíces de genciana (Gentiana lutea), hojas de hamamelis (Hammamelis virginiana), semillas de lino (Linum usitatissimum), semillas entera de trigo (Triticum aestivum), rizomas y raíces de valeriana (Valeriana officinalis) y flores de manzanilla (Matricaria chamomilla). Los análisis realizados a cada planta medicinal comprenden: La descripción morfológica macro- y microscópica, la cuantificación de cenizas totales, el contenido de sustancias extraíbles, la pérdida de peso por secado, el contenido de aceites esenciales y la identificación por cromatografía de capa fina de marcadores taxonómicos