Ketocarotenoids adonirubin and adonixanthin: Properties, health benefits, current technologies, and emerging challenges.

Given their multifaceted roles, carotenoids have garnered significant scientific interest, resulting in a comprehensive and intricate body of literature that occasionally presents conflicting findings concerning the proper characterization, quantification, and bioavailability of these compounds. Nevertheless, it is undeniable that the pursuit of novel carotenoids remains a crucial endeavor, as their diverse properties, functionalities and potential health benefits make them invaluable natural resources in agri-food and health promotion through the diet. In this framework, particular attention is given to ketocarotenoids, viz., astaxanthin (one of them) stands out for its possible multifunctional role as an antioxidant, anticancer, and antimicrobial agent. It has been widely explored in the market and utilized in different applications such as nutraceuticals, food additives, among others. Adonirubin and adonixanthin can be naturally found in plants and microorganisms. Due to the increasing significance of natural-based products and the remarkable opportunity to introduce these ketocarotenoids to the market, this review aims to provide an expert overview of the pros and cons associated with adonirubin and adonixanthin.

Peptide-Functionalized and Drug-Loaded Tomato Bushy Stunt Virus Nanoparticles Counteract Tumor Growth in a Mouse Model of Shh-Dependent Medulloblastoma.

Sonic hedgehog medulloblastoma (SHH-MB) accounts for 25-30% of all MBs, and conventional therapy results in severe long-term side effects. New targeted therapeutic approaches are urgently needed, drawing also on the fields of nanoparticles (NPs). Among these, plant viruses are very promising, and we previously demonstrated that tomato bushy stunt virus (TBSV), functionalized on the surface with CooP peptide, specifically targets MB cells. Here, we tested the hypothesis that TBSV-CooP can specifically deliver a conventional chemotherapeutic drug (i.e., doxorubicin, DOX) to MB in vivo. To this aim, a preclinical study was designed to verify, by histological and molecular methods, if multiple doses of DOX-TBSV-CooP were able to inhibit tumor progression of MB pre-neoplastic lesions, and if a single dose was able to modulate pro-apoptotic/anti-proliferative molecular signaling in full-blown MBs. Our results demonstrate that when DOX is encapsulated in TBSV-CooP, its effects on cell proliferation and cell death are similar to those obtained with a five-fold higher dose of non-encapsulated DOX, both in early and late MB stages. In conclusion, these results confirm that CooP-functionalized TBSV NPs are efficient carriers for the targeted delivery of therapeutics to brain tumors.

Targeting of Tomato Bushy Stunt Virus with a Genetically Fused C-End Rule Peptide.

Homing peptides are widely used to improve the delivery of drugs, imaging agents, and nanoparticles (NPs) to their target sites. Plant virus-based particles represent an emerging class of structurally diverse nanocarriers that are biocompatible, biodegradable, safe, and cost-effective. Similar to synthetic NPs, these particles can be loaded with imaging agents and/or drugs and functionalized with affinity ligands for targeted delivery. Here we report the development of a peptide-guided Tomato Bushy Stunt Virus (TBSV)-based nanocarrier platform for affinity targeting with the C-terminal C-end rule (CendR) peptide, RPARPAR (RPAR). Flow cytometry and confocal microscopy demonstrated that the TBSV-RPAR NPs bind specifically to and internalize in cells positive for the peptide receptor neuropilin-1 (NRP-1). TBSV-RPAR particles loaded with a widely used anticancer anthracycline, doxorubicin, showed selective cytotoxicity on NRP-1-expressing cells. Following systemic administration in mice, RPAR functionalization conferred TBSV particles the ability to accumulate in the lung tissue. Collectively, these studies show the feasibility of the CendR-targeted TBSV platform for the precision delivery of payloads.

In vitro antioxidant and anti-inflammatory activity of an oleuropein-enriched extract obtained from olives leaves on BME-UV1 cells.

In this in vitro study, for the first time was evaluated the antioxidant and anti-inflammatory effect of an Oleuropein-enriched extract (OleE) on bovine mammary epithelial cell line (BME-UV1). OleE was obtained from olives leaves and characterized by HPLC and NMR analysis. Cell viability test indicated that OleE at concentrations of 7.8 up to 250 µg/mL did not exert cytotoxic effect. At concentration of 31.2 up to 250 µg/mL, a dose dependent reduction of ROS production induced by hydrogen peroxide was observed. In addition, OleE at 62.5, 125 and 250 µg/mL showed a dose-dependent reduction in gene expression of TNF, IL1B, and IL10 after exposure to LPS. The downregulation of ROS production and cytokines expression in BME-UV1 by OleE confirmed the antioxidant and anti-inflammatory properties. In vivo experiments will be necessary for future applications of OleE as natural feed supplement in dairy cattle to reduce incidence of oxidative stress in peripartal period.

Rhus Coriaria L. Extract: Antioxidant Effect and Modulation of Bioenergetic Capacity in Fibroblasts from Parkinson's Disease Patients and THP-1 Macrophages.

Sumac, Rhus coriaria L., is a Mediterranean plant showing several useful properties, such as antioxidant and neuroprotective effects. Currently, there is no evidence about its possible neuroprotective action in Parkinson's disease (PD). We hypothesized that sumac could modulate mitochondrial functionality in fibroblasts of familial early-onset PD patients showing PARK2 mutations. Sumac extract volatile profile, polyphenolic content and antioxidant activity have been previously characterized. We evaluated ROS and ATP levels on sumac-treated patients' and healthy control fibroblasts. In PD fibroblasts, all treatments were effective in reducing H2O2 levels, while patients' ATP content was modulated differently, probably due to the varying mutations in the PARK2 gene found in individual patients which are also involved in different mitochondrial phenotypes. We also investigated the effect of sumac extract on THP-1-differentiated macrophages, which show different embryogenic origin with respect to fibroblasts. In THP-1 macrophages, sumac treatment determined a reduction in H2O2 levels and an increase in the mitochondrial ATP content in M1, assuming that sumac could polarize the M1 to M2 phenotype, as demonstrated with other food-derived compounds rich in polyphenols. In conclusion, Rhus coriaria L. extracts could represent a potential nutraceutical approach to PD.

Polyphenols Extracts from Oil Production Waste Products (OPWPs) Reduce Cell Viability and Exert Anti-Inflammatory Activity via PPARγ Induction in Colorectal Cancer Cells.

Olive oil production is associated with the generation of oil production waste products (OPWPs) rich in water-soluble polyphenols that represent serious environmental problems. Yet OPWPs can offer new opportunities by exploiting their bioactive properties. In this study, we chemically characterized OPWPs polyphenolic extracts and investigated their biological activities in normal and colorectal cancer cells. Hydroxytyrosol (HTyr), the major constituent of these extracts, was used as the control. We show that both HTyr and the extracts affect cell viability by inducing apoptosis and cell cycle arrest. They downregulate inflammation by impairing NF-κB phosphorylation and expression of responsive cytokine genes, as TNF-α and IL-8, at both mRNA and protein levels, and prevent any further increase elicited by external challenges. Mechanistically, HTyr and the extracts activate PPARγ while hampering pro-inflammatory genes expression, acting as a specific agonist, likely through a trans-repression process. Altogether, OPWPs polyphenolic extracts show stronger effects than HTyr, conceivably due to additive or synergistic effects of all polyphenols contained. They display anti-inflammatory properties and these results may pave the way for improving OPWPs extraction and enrichment methods to reduce the environmental impact and support their use to ameliorate the inflammation associated with diseases and tumors.

Phytochemical Characterization of Rhus coriaria L. Extracts by Headspace Solid-Phase Micro Extraction Gas Chromatography, Comprehensive Two-Dimensional Liquid Chromatography, and Antioxidant Activity Evaluation.

Rhus coriaria L. (Anacardiaceae), commonly known as sumac, has been used since ancient times for many different applications, and nowadays is used mostly as a spice obtained from its in the Mediterranean and the Middle ground fruits and employed for flavoring and garnishing food, predominantly Eastern regions. Traditionally, sumac has been also used in popular medicine for the treatment of many ailments including hemorrhoids, wound healing, diarrhea, ulcers, and eye inflammation. Sumac drupes are indeed rich in various classes of phytochemicals including organic acids, flavonoids, tannins, and others, which are responsible of their powerful antioxidant capacity, from which treatment of many common diseases such as cardiovascular disease, diabetes, and cancer could benefit. In this work we evaluated the influence of fruit ripeness, conservation, and processing. To this aim, a phytochemical characterization of six different samples of Rhus coriaria L. was carried out. Specifically, headspace solid-phase micro extraction gas chromatography coupled to mass spectrometry and comprehensive two-dimensional liquid chromatography coupled to photodiode array and mass spectrometry detection, were employed. A total of 263 volatile compounds, including terpene hydrocarbons, acids, and aldehydes, as well as 83 polyphenolic compounds, mainly gallic acid derivatives, were positively identified. All samples showed a significant antioxidant activity by means of oxygen radical absorbance capacity, in line with their polyphenolic content and composition. Such findings set a solid ground to support the utilization of this plant as an attractive target for novel nutraceutical approaches and for drug discovery.

Tomato Bushy Stunt Virus Nanoparticles as a Platform for Drug Delivery to Shh-Dependent Medulloblastoma.

Medulloblastoma (MB) is a primary central nervous system tumor affecting mainly young children. New strategies of drug delivery are urgent to treat MB and, in particular, the SHH-dependent subtype-the most common in infants-in whom radiotherapy is precluded due to the severe neurological side effects. Plant virus nanoparticles (NPs) represent an innovative solution for this challenge. Tomato bushy stunt virus (TBSV) was functionally characterized as a carrier for drug targeted delivery to a murine model of Shh-MB. The TBSV NPs surface was genetically engineered with peptides for brain cancer cell targeting, and the modified particles were produced on a large scale using Nicotiana benthamiana plants. Tests on primary cultures of Shh-MB cells allowed us to define the most efficient peptides able to induce specific uptake of TBSV. Immunofluorescence and molecular dynamics simulations supported the hypothesis that the specific targeting of the NPs was mediated by the interaction of the peptides with their natural partners and reinforced by the presentation in association with the virus. In vitro experiments demonstrated that the delivery of Doxorubicin through the chimeric TBSV allowed reducing the dose of the chemotherapeutic agent necessary to induce a significant decrease in tumor cells viability. Moreover, the systemic administration of TBSV NPs in MB symptomatic mice, independently of sex, confirmed the ability of the virus to reach the tumor in a specific manner. A significant advantage in the recognition of the target appeared when TBSV NPs were functionalized with the CooP peptide. Overall, these results open new perspectives for the use of TBSV as a vehicle for the targeted delivery of chemotherapeutics to MB in order to reduce early and late toxicity.

Hydroxytyrosol and Oleuropein-Enriched Extracts Obtained from Olive Oil Wastes and By-Products as Active Antioxidant Ingredients for Poly (Vinyl Alcohol)-Based Films.

Oxidative stability of food is one of the most important parameters affecting integrity and consequently nutritional properties of dietary constituents. Antioxidants are widely used to avoid deterioration during transformation, packaging, and storage of food. In this paper, novel poly (vinyl alcohol) (PVA)-based films were prepared by solvent casting method adding an hydroxytyrosol-enriched extract (HTyrE) or an oleuropein-enriched extract (OleE) in different percentages (5, 10 and 20% w/w) and a combination of both at 5% w/w. Both extracts were obtained from olive oil wastes and by-products using a sustainable process based on membrane technologies. Qualitative and quantitative analysis of each sample carried out by high performance liquid chromatography (HPLC) and nuclear resonance magnetic spectroscopy (NMR) proved that the main components were hydroxytyrosol (HTyr) and oleuropein (Ole), respectively, two well-known antioxidant bioactive compounds found in Olea europaea L. All novel formulations were characterized investigating their morphological, optical and antioxidant properties. The promising performances suggest a potential use in active food packaging to preserve oxidative-sensitive food products. Moreover, this research represents a valuable example of reuse and valorization of agro-industrial wastes and by-products according to the circular economy model.

Non-COVID-19 patients in times of pandemic: Emergency department visits, hospitalizations and cause-specific mortality in Northern Italy.

The COVID-19 pandemic forced healthcare services organization to adjust to mutating healthcare needs. Not exhaustive data are available on the consequences of this on non-COVID-19 patients. The aim of this study was to assess the impact of the pandemic on non-COVID-19 patients living in a one-million inhabitants' area in Northern Italy (Bologna Metropolitan Area-BMA), analyzing time trends of Emergency Department (ED) visits, hospitalizations and mortality. We conducted a retrospective observational study using data extracted from BMA healthcare informative systems. Weekly trends of ED visits, hospitalizations, in- and out-of-hospital, all-cause and cause-specific mortality between December 1st, 2019 to May 31st, 2020, were compared with those of the same period of the previous year. Non-COVID-19 ED visits and hospitalizations showed a stable trend until the first Italian case of COVID-19 has been recorded, on February 19th, 2020, when they dropped simultaneously. The reduction of ED visits was observed in all age groups and across all severity and diagnosis groups. In the lockdown period a significant increase was found in overall out-of-hospital mortality (43.2%) and cause-specific out-of-hospital mortality related to neoplasms (76.7%), endocrine, nutritional and metabolic (79.5%) as well as cardiovascular (32.7%) diseases. The pandemic caused a sudden drop of ED visits and hospitalizations of non-COVID-19 patients during the lockdown period, and a concurrent increase in out-of-hospital mortality mainly driven by deaths for neoplasms, cardiovascular and endocrine diseases. As recurrencies of the COVID-19 pandemic are underway, the scenario described in this study might be useful to understand both the population reaction and the healthcare system response at the early phases of the pandemic in terms of reduced demand of care and systems capability in intercepting it.

Anti-proliferative effect of pomegranate peel extracts on bovine peripheral blood mononuclear cells (PBMCs).

Pomegranate peel extracts prepared in our laboratories from a waste of juice fruit processing were tested on bovine peripheral blood mononuclear cells to evaluate the effects on viability, oxidative stress and proliferation. The (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay pointed out that the extracts were not cytotoxic at the tested concentrations (0.1, 1.0, and 10 µg/mL). A moderate protective effect against Reactive Oxygen Species production induced by hydrogen peroxide or lipopolysaccharide and a significant anti-proliferative activity against proliferation induced by concanavalin A were observed on cell lines treated with the extracts at 10 µg/mL. Based on these results, pomegranate peel extracts seem promising as feed supplement for dairy cattle, in particular around calving, when the animals are subjected to an increase of the metabolic activity, responsible for oxidative stress and diseases. However, in vivo studies are needed to investigate the stability of the extracts across the bovine gastrointestinal tract barrier.

Prevention and treatment of autoimmune diseases with plant virus nanoparticles.

Plant viruses are natural, self-assembling nanostructures with versatile and genetically programmable shells, making them useful in diverse applications ranging from the development of new materials to diagnostics and therapeutics. Here, we describe the design and synthesis of plant virus nanoparticles displaying peptides associated with two different autoimmune diseases. Using animal models, we show that the recombinant nanoparticles can prevent autoimmune diabetes and ameliorate rheumatoid arthritis. In both cases, this effect is based on a strictly peptide-related mechanism in which the virus nanoparticle acts both as a peptide scaffold and as an adjuvant, showing an overlapping mechanism of action. This successful preclinical testing could pave the way for the development of plant viruses for the clinical treatment of human autoimmune diseases.

Hydroxytyrosol stimulates neurogenesis in aged dentate gyrus by enhancing stem and progenitor cell proliferation and neuron survival.

The dentate gyrus of the hippocampus is one of two brain areas generating throughout life new neurons, which contribute to the formation of episodic/associative memories. During aging, the production of new neurons decreases and a cognitive decline occurs. Dietary factors influence neuronal function and synaptic plasticity; among them the phenolic compound hydroxytyrosol (HTyr), present in olive oil, displays neuroprotective effects. As age impacts primarily on the hippocampus-dependent cognitive processes, we wondered whether HTyr could stimulate hippocampal neurogenesis in vivo in adult and aged wild-type mice as well as in the B-cell translocation 1 gene (Btg1) knockout mouse model of accelerated neural aging. We found that treatment with HTyr activates neurogenesis in the dentate gyrus of adult, aged, and Btg1-null mice, by increasing survival of new neurons and decreasing apoptosis. Notably, however, in the aged and Btg1-null dentate gyrus, HTyr treatment also stimulates the proliferation of stem and progenitor cells, whereas in the adult dentate gyrus HTyr lacks any proliferative effect. Moreover, the new neurons generated in aged mice after HTyr treatment are recruited to existing circuits, as shown by the increase of BrdU+ /c-fos+ neurons. Finally, HTyr treatment also reduces the markers of aging lipofuscin and Iba1. Overall, our findings indicate that HTyr treatment counteracts neurogenesis decline during aging.

Antioxidant and anti-inflammatory effects of pomegranate peel extracts on bovine mammary epithelial cells BME-UV1.

Pomegranate peel extracts (PPE) were tested for the first time on BME-UV1, a valid cellular model to study the bovine mammary epithelial metabolism, to evaluate the effects on the oxidative stress and inflammatory status. Based on the statistical analysis of MTT data, PPE at 0.1, 1.0 and 10 µg/mL resulted not cytotoxic after 24 h, 48 h and 7 days of treatment. At the same concentrations, PPE induced a reduction of ROS production elicited by the addition of hydrogen peroxide or lipopolysaccharide evidencing an antioxidant effect confirmed also by a decrease of malondialdehyde. At 10 µg/mL, PPE reduced pro-inflammatory cytokines expressions showing an anti-inflammatory effect on BME-UV1 treated with lipopolysaccharide. Although in vivo experiments are necessary, the results of this study are promising for future applications of PPE as feed supplement for dairy cattle, in particular around calving, when the animals are more subject to oxidative stress and inflammatory diseases.

In vitro studies on anti-inflammatory activities of kiwifruit peel extract in human THP-1 monocytes.

ETHNOPHARMACOLOGICAL RELEVANCE: Kiwifruit is native to eastern China and many are the references about the consumption of fruits and fruits extracts of the Actinidia plants in Chinese traditional medicine as therapeutic food supplements to prevent and/or counteract numerous disorders including inflammation-related diseases like cancer. AIM OF THE STUDY: Aim of the present work was to obtain a kiwifruit peel extract, rich in polyphenols, and to explore the anti-inflammatory potential by analyzing its capability to target multiple pathways involved in monocyte-mediated inflammatory response. MATERIALS AND METHODS: The extract was obtained from the fruit peel of Actinidia deliciosa (A.Chev.) C.F.Liang & A.R.Ferguson, cv Hayward and characterized by HPLC-DAD-ESI-MS. Lipopolysaccharide-stimulated THP-1 monocytes were used as a model of human inflammation in vitro. RESULTS: Analytical data evidenced that procyanidins resulted the main polyphenols present in the extract, representing the 92% w/w of the total. The extract inhibited the production of inflammatory molecules such as IL-6, IL-1ß, TNF-α pro-inflammatory cytokines, HMGB1 danger signal and granzyme B serine protease by activated monocytes. In particular, an inhibitory activity of 81%, 68%, 63%, 76% and 60% on the extracellular release of IL-6, IL-1ß, TNF-α, HMGB1 and granzyme B, respectively, was observed by western blot analysis. Moreover, the extract prevented STAT3 activation and promoted autophagy. CONCLUSIONS: The reported findings demonstrated a strong and broad anti-inflammatory profile of the kiwifruit peel extract, which makes it a promising preventive and therapeutic natural ingredient for nutraceutical, cosmetic and pharmaceutical formulations to counteract multiple inflammatory disorders.

Cocoa Polyphenols: Chemistry, Bioavailability and Effects on Cardiovascular Performance.

This review gives an overview of the phenolic compounds composition of cocoa beans and their modification during manufacturing processes to the final products. Recently published papers dealing with the qualitative and quantitative analysis of the different classes of cocoa phenolic compounds will be discussed. Modifications of the qualitative profile and amount of phenolic compounds in cocoa after the main processes of production chain, fermentation, drying, roasting, and alkalization, will be described. The second part will focus on some of the biological effects described for cocoa phenolic compounds in vitro and in vivo. In particular, the effects of cocoa flavanols on cardiovascular health and endothelial function have been extensively investigated over the last decades, with interesting results from nutritional intervention trials and molecular studies. A few recent updates on the role of cocoa and chocolate consumption on sport performances will be reported.

A biodistribution study of two differently shaped plant virus nanoparticles reveals new peculiar traits.

Self-assembling plant virus nanoparticles (pVNPs) have started to be explored as nanometre-sized objects for biomedical applications, such as vaccine or drug delivery and imaging. Plant VNPs may be ideal tools in terms of biocompatibility and biodegradability endowed with a wide diversity of symmetries and dimensions, easy chemical/biological engineering, and rapid production in plants. Recently, we defined that icosahedral Tomato bushy stunt virus (TBSV) and filamentous Potato virus X (PVX) are neither toxic nor teratogenic. We report here the results of an interdisciplinary study aimed to define for the first time the biodistribution of unlabelled, unpegylated, underivatized TBSV and PVX by proved detecting antibodies. These data add new insights on the in vivo behaviour of these nano-objects and demonstrate that the pVNPs under scrutiny are each intrinsically endowed with peculiar properties foreshadowing different applications in molecular medicine.

Calcium ions modulate the mechanics of tomato bushy stunt virus.

Viral particles are endowed with physicochemical properties whose modulation confers certain metastability to their structures to fulfill each task of the viral cycle. Here, we investigate the effects of swelling and ion depletion on the mechanical stability of individual tomato bushy stunt virus nanoparticles (TBSV-NPs). Our experiments show that calcium ions modulate the mechanics of the capsid: the sequestration of calcium ions from the intracapsid binding sites reduces rigidity and resilience in ∼24% and 40%, respectively. Interestingly, mechanical deformations performed on native TBSV-NPs induce an analogous result. In addition, TBSV-NPs do not show capsomeric vacancies after surpassing the elastic limit. We hypothesize that even though there are breakages among neighboring capsomers, RNA-capsid protein interaction prevents the release of capsid subunits. This work shows the mechanical role of calcium ions in viral shell stability and identifies TBSV-NPs as malleable platforms based on protein cages for cargo transportation at the nanoscale.

In vitro and in vivo toxicity evaluation of plant virus nanocarriers.

The use of biological self-assembling materials, plant virus nanoparticles in particular, appears very intriguing as it allows a great choice of symmetries and dimensions, easy chemical and biological engineering of both surface and/or internal cavity as well as safe and rapid production in plants. In this perspective, we present an initial evaluation of the safety profile of two structurally different plant viruses produced in Nicotiana benthamiana L. plants: the filamentous Potato virus X and the icosahedral Tomato bushy stunt virus. In vitro haemolysis assay was used to test the cytotoxic effects, which could arise by pVNPs interaction with cellular membranes, while early embryo assay was used to evaluate toxicity and teratogenicity in vivo. Data indicates that these structurally robust particles, still able to infect plants after incubation in serum up to 24h, have neither toxic nor teratogenic effects in vitro and in vivo. This work represents the first safety-focused characterization of pVNPs in view of their possible use as drug delivery carriers.

Construction of a synthetic infectious cDNA clone of Grapevine Algerian latent virus (GALV-Nf) and its biological activity in Nicotiana benthamiana and grapevine plants.

BACKGROUND: Grapevine Algerian latent virus (GALV) is a tombusvirus first isolated in 1989 from an Algerian grapevine (Vitis spp.) plant and more recently from water samples and commercial nipplefruit and statice plants. No further reports of natural GALV infections in grapevine have been published in the last two decades, and artificial inoculations of grapevine plants have not been reported. We developed and tested a synthetic GALV construct for the inoculation of Nicotiana benthamiana plants and different grapevine genotypes to investigate the ability of this virus to infect and spread systemically in different hosts. METHODS: We carried out a phylogenetic analysis of all known GALV sequences and an epidemiological survey of grapevine samples to detect the virus. A GALV-Nf clone under the control of the T7 promoter was chemically synthesized based on the full-length sequence of the nipplefruit isolate GALV-Nf, the only available sequence at the time the project was conceived, and the infectious transcripts were tested in N. benthamiana plants. A GALV-Nf-based binary vector was then developed for the agroinoculation of N. benthamiana and grapevine plants. Infections were confirmed by serological and molecular analysis and the resulting ultrastructural changes were investigated in both species. RESULTS: Sequence analysis showed that the GALV coat protein is highly conserved among diverse isolates. The first epidemiological survey of cDNAs collected from 152 grapevine plants with virus-like symptoms did not reveal the presence of GALV in any of the samples. The agroinoculation of N. benthamiana and grapevine plants with the GALV-Nf binary vector promoted efficient infections, as revealed by serological and molecular analysis. The GALV-Nf infection of grapevine plants was characterized in more detail by inoculating different cultivars, revealing distinct patterns of symptom development. Ultrastructural changes induced by GALV-Nf in N. benthamiana were similar to those induced by tombusviruses in other hosts, but the cytopathological alterations in grapevine plants were less severe. CONCLUSIONS: This is the first report describing the development of a synthetic GALV-Nf cDNA clone, its artificial transmission to grapevine plants and the resulting symptoms and cytopathological alterations.