Larrea divaricata a native Argentine plant with potential activity against SARS-CoV-2? / ¿Larrea divaricata una planta nativa argentina con actividad potencial sobre SARS-CoV-2?

Larrea divaricata Cav. is an autochthonous South American plant popularly used in inflammatory and infectious diseases with reported anti - inflammatory, immunomodulatory, antimicrobial and antioxidant activities. Covid - 19 is an infection ca used by the severe acute respiratory syndrome coronavirus 2 (SARS - CoV - 2). This virus can cause pneumonia and even death in about 5% of the cases. The objective of the article was to demonstrate, through a literature review, that L. divaricata has sufficie nt attributes to be assayed against SARS - CoV - 2. For this, the chemical composition, reported activities and docking studies were taken into account. This review demonstrated that the plant extracts are capable of inhibiting the proliferation of fungi, bact eria and viruses and that they exert anti - inflammatory and immunomodulatory actions in different " in vitro " and " in vivo " models. These results suggest that the plant is a good candidate to be studied for the prevention and/or treatment of SARS - CoV - 2.

Larrea divaricata Cav. es una planta autóctona Sudamericana, utilizada popularmente en enfermedades inflamatorias e infecciosas, con activida d anti - inflamatoria, inmunomoduladora, antimicrobiana y antioxidante reportada. El Covid - 19 es una infección causada por una cepa de coronavirus, SARS - CoV - 2 (coronavirus tipo 2 causante del síndrome respiratorio agudo severo). Este virus puede originar neu monía e incluso la muerte en alrededor del 5% de los casos. Nuestro objetivo fue demostrar, a través de una revisión bibliográfica, que esta planta tiene atributos suficientes para ser ensayada en estudios contra SARS - CoV - 2. Se tuvo en cuenta la composici ón química, los antecedentes científicos y los estudios de acoplamiento molecular. Esta revisión permitió demostrar que extractos de la planta son capaces de inhibir la proliferación de hongos, bacterias y virus y que presentan acción anti - inflamatoria en diferentes modelos " in vitro " e " in vivo ", lo que los hace candidatos a ser estudiados en la prevención y/o tratamiento de la infección contra SARS - CoV - 2.

Vicenin-2 and vitexin participate in the in vitromodulation of the anti-inflammatory and antioxidant activities exerted by two Urtica circularisextracts / Participación de vicenina-2 y vitexina en la modulación de la actividad anti-inflamatoria in vitro y en la actividad antioxidante de dos extractos de Urtica circularis

Urtica circularis is an Argentinean species traditionally used to treat inflammation symptoms and oxidative stress-related diseases. Considering the uses in folk medicine, the purpose of this work was to evaluate and compare the anti-inflammatory and antioxidant activities of two different U. circularisextracts. The contribution of vicenin-2 and vitexin, two compounds identified in the phytochemical analysis, in the biological activity of the extracts was evaluated. The anti-inflammatory activity of the extracts and the isolated compounds was tested on lipopolysaccharide (LPS)-stimulated macrophages, while the antioxidant activity was evaluated through the 2,2 ́ diphenyl-1-picrylhydrazyl (DPPH) radical and 2,2 ́-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) diammonium salt (ABTS) scavenging activities. The popular uses of both extracts were validated, i.e., the use of U. circularis ethanol extract for the treatment of inflammation, and the use of the aqueous extract to treat oxidative stress related-diseases. The differences in the biological activities observed between the extracts are probably due to qualitative and/or quantitative differences in the chemical composition and/or the occurrence of synergism between compounds.

Urtica circularis es una especie argentina utilizada para tratar los síntomas de la inflamación y enfermedades relacionadas con el estrés oxidativo. El objetivo de este trabajo fue evaluar y comparar las actividades anti-inflamatoria y antioxidante de dos extractos teniendo en cuenta su uso popular. Además, se analizó la participación de vicenina-2 y vitexina, compuestos identificados en el análisis fitoquímico, en la actividad de los extractos. La actividad anti-inflamatoria fue evaluada en macrófagos activados con lipopolisacárido (LPS). Se midió su actividad antioxidante con los métodos del 1,1,difenil-2-picril-hidrazilo (DPPH) y del ácido2,2 ́azinobis-3 etilbenzotialzolin-6-sulfónico (ABTS). Los usos populares de ambos extractos fueron validados: el extracto etanólico para la inflamación y el extracto acuoso para el tratamiento de enfermedades relacionadas con el estrés oxidativo. Las diferencias en las actividades biológicas observadas entre los extractos están probablemente relacionadas con diferencias cualitativas y/o cuantitativas en su composición química y/o a la presencia de sinergismo entre compuestos

Larrea divaricata Cav: scientific evidence showing its beneficial effects and its wide potential application / Larrea divaricata Cav: evidencia específica mostrando sus efectos beneficiosos y su amplia aplicación potencial

Larrea divaricata Cav. (jarilla) (Zygophyllaceae) is used in Argentinean folk medicine. It contains nordihydroguaiaretic acid (NDGA), a lignan with nefrotoxic and hepatotoxic effects. The presence of NDGA converts controversial the use of L. divaricata. The amount of NDGA is higher in alcoholic extracts than in aqueous extracts (AE). The last 20 years had a great advance on the use of AE to treat different conditions in a safe manner. In this review, we present the scientific results tending to confirm the potential beneficial effects of the AE on human health. The anti-proliferative effects of AE of L. divaricata have been assayed on a tumor lymphoid line (BW 5147) and the pathways involved in such effects were described. The anti-microbial activity was determined by tests for bacteria and fungus. The anti-inflammatory activity was assayed by using carrageen and TPA induced-inflammation tests. The Immunomodulatory effects were investigated ¯in vivo and ¯in vitro on mice. Sub-fractions of aqueous extracts were obtained and analyzed. The immunogenicity of proteins from crude AE was characterized and antioxidant and nutritional activity were studied. The effect of an AE on hair loss was assayed. In summary, AE from L. divaricata has pharmacological activities including anti-microbial, anti-inflammatory, anti-cancer effects.

Larrea divaricata Cav. (Jarilla) (Zygophyllaceae) es utilizada en medicina popular Argentina. Contiene ácido nordihidroguaiarético (NDGA), un lignano con efectos nefrotóxicos y hepatotóxicos. La presencia de NDGA hace controvertido el uso de L. divaricata. La cantidad de NDGA es mayor en extractos alcohólicos que en extractos acuosos (EA). Los últimos 20 años han tenido un gran avance en el uso de EA para el tratamiento de diferentes condiciones en forma segura. En esta revisión se presentan resultados científicos que confirman los efectos potencialmente beneficiosos de los EA sobre la salud humana. Los efectos anti-proliferativos se han ensayado en una línea de tumor linfoide, así como los mecanismos involucrados. La actividad anti-microbiana se determinó usando pruebas para bacterias y hongos. La actividad anti-inflamatoria fue evaluada mediante el uso de inflamación inducida por carragenina y TPA. Los efectos inmunomoduladores fueron investigados "in vivo" e "in vitro" en ratones. Sub-fracciones de los EA fueron obtenidos y analizados. La inmunogenicidad de las proteínas del EA crudo se caracterizaron y se estudiaron las actividades antioxidantes nutricionales. Además, se ensayó el efecto del EA en la caída del cabello. En resumen, los EA de L. divaricata presentan actividades farmacológicas como por ejemplo, anti-microbiana, anti-inflamatoria y efectos anti-cancerígenos.

"In vivo" and "in vitro" antitumoral action of Larrea divaricata cav

We previously reported that aqueous extract of Larrea divaricata Cav had an antiproliferative activity upon tumoral lymphoid cells (BW 5147), without affecting normal immunity. To determine the probable mechanism of the inhibitory action of the extract upon cell growth, the participation of intracellular signals involved in the inhibition of cell proliferation, namely the activation of adenylate cyclase system was studied. The production of cyclic 3', 5 adenosine monophosphate (cAMP) in presence and absence of extract was analized. The extract increased the cAMP levels, but neither the cAMP production nor the inhibitory effect of the extract on proliferation were blocked by a beta adrenergic receptor antagonist (propranolol) or by histaminergic receptor antagonistis (cimetidine and mepyramine). So, we concluted that the antiproliferative activity of the extract of BW 5147 cells would be mediated by an increase in cAMP intracellular levels no related to the activation of the membrane receptors here studied. In parallel, the extract was administered to a pregnant rat with a spontaneous mammarian carcinoma and "in vivo"antitumoral activity was found.