Efficacy of Bidens pilosa Extract against Herpes Simplex Virus Infection In Vitro and In Vivo

Structural insights into modeling of hepatitis B virus reverse transcriptase and identification of its inhibitors from potential medicinal plants of Western Ghats: an in silico and in vitro study

The present study was proposed to model full-length HBV-RT and investigate the intermolecular interactions of known inhibitor and libraries of phytocompounds to probe the potential natural leads by in silico and in vitro studies. Homology modeling of RT was performed by Phyre2 and Modeller and virtual screening of ligands implemented through POAP pipeline. Molecular dynamics (MD) simulation (100 ns) and MM-GBSA calculations were performed using Schrodinger Desmond and Prime, respectively. Phytocompounds probable host protein targets gene set pathway enrichment and network analysis were executed by KEGG database and Cytoscape software. Prioritized plant extracts/enriched fraction LC-MS analysis was performed and along with pure compound, RT inhibitory activity, time-dependent HBsAg and HBeAg secretion, and intracellular HBV DNA, and pgRNA by qRT-PCR was performed in HepG2.2.15 cell line. Among the screened chemical library of 268 phytocompounds from 18 medicinal plants, 15 molecules from Terminalia chebula (6), Bidens pilosa (5), and Centella asiatica (4)) were identified as potential inhibitors of YMDD and RT1 motif of HBV-RT. MD simulation demonstrated stable interactions of 15 phytocompounds with HBV-RT, of which 1,2,3,4,6-Pentagalloyl Glucose (PGG) was identified as lead molecule. Out of 15 compounds, 11 were predicted to modulate 39 proteins and 15 molecular pathways associated with HBV infection. TCN and TCW (500 µg/mL) showed potent RT inhibition, decreased intracellular HBV DNA, and pgRNA, and time-dependent inhibition of HBsAg and HBeAg levels compared to PGG and Tenofovir Disoproxil Fumarate. We propose that the identified lead molecules from T. chebula as promising and cost-effective moieties for the management of HBV infection.Communicated by Ramaswamy H. Sarma.

Prospective Asian plants with corroborated antiviral potentials: Position standing in recent years

Viral diseases are extremely widespread infections caused by viruses. Amongst numerous other illnesses, viral infections have challenged human existence severely. Over the history of mankind, new viruses have emerged and presented us with new tests. The range of viral infections varies from familiar infectious diseases such as the common cold, flu, and warts to severe ailments such as AIDS, Ebola, and COVID-19. The world has been racing to find an effective cure for the newly evolving viruses. Toxic effects, non-selectivity, drug resistance, and high price are the most common complications of conventional treatment procedures. Nature is a marvelous source of phytoconstituents with incredible varieties of biological activities. By tradition, medicinal plants have been utilized for the treatment of countless infectious diseases worldwide, some of which contain a broad spectrum of activities. Modern drug discovery and development techniques offer highly efficient separation techniques, inauguration of vector-based schemes where the original infectious virus is cloned to the non-infectious one for antiviral screening targets. The objective of the review was to gather available data on 20 both cultivated and native plants of Asia giving antiviral activities and provide comprehensive information on the phytochemical analysis of the plants and potential antiviral compounds isolated from these plants.

Mangiferin: A promising natural xanthone from Mangifera indica for the control of acyclovir - resistant herpes simplex virus 1 infection

Mangiferin is found in many plant species as the mango tree (Mangifera indica) with ethnopharmacological applications and scientific evidence. The emergence of resistant herpes simplex virus (HSV) strains to Acyclovir (ACV) has encouraged the search for new drugs. We investigated the in vitro and in vivo activity of mangiferin obtained from M. indica against ACV-resistant HSV-1 (AR-29) and sensitive (KOS) strains. The in vitro activity was performed under varying treatment protocols. The substance showed a CC₅₀ > 500 μg/mL and IC₅₀ of 2.9 μg/mL and 3.5 μg/mL, respectively, for the AR-29 and KOS strains. The in vivo activity was performed in Balb/c mice treated with 0.7% topical mangiferin formulation. This formulation inhibited most effectively the AR-29 strain, attenuated the lesions, postponed their appearance or enhanced healing, in comparison to control group. We demonstrated the potentiality of mangiferin from M. indica to control HSV replication with emphasis to ACV-resistant infection.

Bidens pilosa Extract Administered after Symptom Onset Attenuates Glial Activation, Improves Motor Performance, and Prolongs Survival in a Mouse Model of Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is a late-onset neurodegenerative disorder characterized by progressive paralysis resulting from the death of upper and lower motor neurons. There is currently no effective pharmacological treatment for ALS, and the two approved drugs riluzole and edaravone have limited effects on the symptoms and only slightly prolong the life of patients. Therefore, the development of effective therapeutic strategies is of paramount importance. In this study, we investigated whether Miyako Island Bidens pilosa (MBP) can alleviate the neurological deterioration observed in a superoxide dismutase-1 G93A mutant transgenic mouse (G93A mouse) model of ALS. We orally administered 2 g/kg/day of MBP to G93A mice at the onset of symptoms of neurodegeneration (15 weeks old) until death. Treatment with MBP markedly prolonged the life of ALS model mice by approximately 20 days compared to that of vehicle-treated ALS model mice and significantly improved motor performance. MBP treatment prevented the reduction in SMI32 expression, a neuronal marker protein, and attenuated astrocyte (detected by GFAP) and microglia (detected by Iba-1) activation in the spinal cord of G93A mice at the end stage of the disease (18 weeks old). Our results indicate that MBP administered after the onset of ALS symptoms suppressed the inflammatory activation of microglia and astrocytes in the spinal cord of the G93A ALS model mice, thus improving their quality of life. MBP may be a potential therapeutic agent for ALS.

Ethnobotanical study of medicinal plants used by Ribeirinhos in the North Araguaia microregion, Mato Grosso, Brazil

ETHNOPHARMACOLOGICAL IMPORTANCE

Currently, in many traditional communities, such as the riverine community in the North Araguaia microregion (Mato Grosso, Brazil), plant knowledge and use represent the main, if not the only, therapeutic resource for the maintenance of health and/or treatment of diseases. This study aimed to identify and document species of medicinal plants used by local experts from riverine communities in the North Araguaia microregion in Mato Grosso State, and to further chemical and pharmacological studies on species selected based on searches in the relevant literature.

MATERIALS AND METHODS

This is a cross-sectional ethnobotanical study, with non-probabilistic sampling (n =60), that applied the snowball method to select local riverine experts who understand medicinal plant use. Socio-demographic, ethnobotanical and ethnopharmacological data (vernacular name, uses, geographical origin, habit, method of preparation and part used) on medicinal plants were collected during semi-structured interviews. The results were analyzed by descriptive and quantitative means: indices of use-report (UR) were used to select plant species with therapeutic potential.

RESULTS

In total, 309 plant species belonging to 86 botanical families were cited; 73% were native to Brazil, and Fabaceae was the most representative family (11.3%). Arboreal was the predominant life form (37.2%). The leaf was the most used part (28.9%). Infusion was the most commonly reported method of preparation (31.3%). The plants reported in the survey were indicated for 18 of the 22 ICD-10 disease categories. The disease categories most commonly cited were the infectious and parasitic diseases (IPD, 718 UR), digestive system diseases (DSD, 565 UR) and respiratory system diseases (RSD, 504 UR), representing 16.6%, 13.1% and 11.7%, respectively of the total UR. Dysphania ambrosioides L. was the most sighted in the IPD category 50 UR. Copaifera langsdorffii Desf. (133), Lafoensia pacari A. St.-Hil. (131), and Cecropia pachystachya Trécul (126) were the species with the highest UR. Bidens pilosa L., Vernonia ferruginea Less, and L. pacari, respectively, were the most cited native plants used to treat such diseases. Of the 8 investigated native plants, C. langsdorffii, and Brosimum gaudichaudii are the most prominent: in addition to having been widely studied, in terms of phytochemical and pharmacological, these species have been marketed as pharmaceutical products, with associated patent deposits.

CONCLUSIONS

Local riverine experts from the North Araguaia microregion use a wide variety of medicinal plants in self-care health, especially those species used to treat IPD. The therapeutic potential of some of these plants has been scientifically validated; however, there are other species whose pharmacological effects and safety remain to be properly investigated. Thus, the present study, aside from being a basis for future chemical, pharmacological and agronomic bioprospecting studies, may contribute to the development of the management, conservation and sustainable use of medicinal flora in the microregion studied.

Cytopiloyne, a polyacetylenic glucoside from Bidens pilosa, acts as a novel anticandidal agent via regulation of macrophages

ETHNOPHARMACOLOGICAL RELEVANCE

Bidens pilosa, a tropical and sub-tropical herbal plant, is used as an ethnomedicine for bacterial infection or immune modulation in Asia, America and Africa. It has been demonstrated that cytopiloyne (CP), a bioactive polyacetylenic glucoside purified from B. pilosa, increases the percentage of macrophages in the spleen but the specific effects on macrophages remain unclear.

AIM OF THE STUDY

The aim of this study was to evaluate the effects of CP on macrophage activity and host defense in BALB/c mice with Candida parapsilosis infection and investigate the likely mechanisms.

MATERIALS AND METHODS

RAW264.7 cells, a mouse macrophage cell line, were used to assess the effects of CP on macrophage activity by phagocytosis assay, colony forming assay and acridine orange/crystal violet stain. To evaluate the activity of CP against C. parapsilosis, BALB/c mouse infection models were treated with/without CP and histopathological examination was performed. The role of macrophages in the infection model was clarified by treatment with carrageenan, a selective macrophage-toxic agent. RAW264.7 macrophage activities influenced by CP were further investigated by lysosome staining, phagosomal acidification assay, lysosome enzyme activity and PKC inhibitor GF109203X.

RESULTS

The results showed that CP in vitro enhances the ability of RAW264.7 macrophages to engulf and clear C. parapsilosis. In the mouse model, CP treatment improved the survival rate of Candida-infected mice and lowered the severity of microscopic lesions in livers and spleens via a macrophage-dependent mechanism. Furthermore, with CP treatment, the fusion and acidification of phagolysosomes were accelerated and the lysosome enzyme activity of RAW264.7 macrophages was elevated. PKC inhibitor GF109203X reversed the increase in phagocytic activity by CP demonstrating that the PKC pathway is involved in the macrophage-mediated phagocytosis of C. parapsilosis.

CONCLUSIONS

Our data suggested that CP, as an immunomodulator, enhances macrophage activity against C. parapsilosis infections.

Antiherpetic Plants: A Review of Active Extracts, Isolated Compounds, and Bioassays

Herpes simplex is a disease that is widely distributed throughout the world. It is caused by herpes simplex virus type 1 (HSV-1) and simplex virus type 2 (HSV-2). The drugs of choice for treatment are acyclovir (ACV), Penciclovir (PCV) and other guanine analogues, which have the same mechanism of action. However, due to the constant increase of ACV-resistant strains in immunocompromised patients, it is necessary to find new treatment alternatives. It has been shown that natural products are a good alternative for the treatment of these diseases as well as being an excellent source of compounds with anti-herpetic activity, which may be useful for the development of new drugs and act through a mechanism of action different from ACV and PCV. This paper compiles reports on extracts and compounds isolated from plants that have anti-herpetic activity. We present an analysis of the solvents most widely used for extraction from plants as well as cells and commonly used methods for evaluating cytotoxic and anti-herpetic activity. Families that have a higher number of plants with anti-herpetic activity are evaluated, and we also highlight the importance of studies of mechanisms of action of extracts and compounds with anti-herpetic activity.

The antimicrobial agent C31G is effective for therapy for HSV-1 ocular keratitis in the rabbit eye model

The amphoteric C31G solution contains equimolar alkyl dimethlyglycine and alkyl dimethyl amine oxide buffered with citric acid. C31G acts as a broad spectrum antiviral and an antibacterial. No previous in vivo studies have been done to test C31G in an animal model of HSV-1 ocular keratitis. We assessed the anti-herpetic activity of C31G in the rabbit eye model using three treatment groups: (1) 1% trifluorothymidine (TFT); (2) 0.25% C31G plus 0.5% hydroxypropyl methylcellulose (HPMC); and (3) vehicle, 0.5% HPMC. Scarified rabbit corneas were inoculated with the HSV-1 strain McKrae. On post inoculation (PI) day 3, rabbits were placed in three balanced groups based on slit-lamp examination (SLE) scores. Treatment began on PI day 3, five times a day for five consecutive days. In addition to the daily, masked SLE scoring, the eyes were assessed daily for stromal opacity, scleral inflammation, neovascularization, eyelid inflammation, inflammatory discharge, and epiphora. C31G and TFT were very effective in reducing the lesions and pathogenesis associated with HSV-1 ocular keratitis. The vehicle control scores were significantly higher and did not effectively treat HSV-1 keratitis. C31G has the potential to be used to treat herpetic keratitis as well as other herpetic topical lesions in humans.

Amazonian Brazilian medicinal plants described by C.F.P. von Martius in the 19th century

ETHNOPHARMACOLOGICAL RELEVANCE

Information regarding the use of beneficial, native Brazilian plants was compiled by European naturalists during the 19th century. The German botanist C.F.P. von Martius was one of the most prominent naturalists and described the use of several Brazilian plants.

AIM OF THE STUDY

To present data on Amazonian medicinal plants documented by von Martius in his books.

MATERIALS AND METHODS

Data on Amazonian medicinal plants were obtained from three books published by von Martius. Traditional information about these plants was translated from Latin and the cited plant species reorganised according to current taxonomic criteria. Correlated pharmacological studies were obtained from different scientific databases.

RESULTS

A total of 92 native medicinal species from the Amazon were recorded in von Martius' books. These accounts described 117 different medical uses for these plants. Several parts of the plants were used, including many exudates. The principal use of the species recorded was the treatment of dermatological problems, followed by gastro-intestinal, urinary and respiratory disorders. Few species were recorded as purgatives and febrifuges, a result that differs from the observations of other naturalists. The efficacy of the recorded traditional uses has been confirmed for the few species that have been subjected to laboratory studies.

CONCLUSION

The data recorded by the German naturalist von Martius represent a rich, unexplored source of information about the traditional uses of Brazilian plants.