New indole derivatives from endophytic fungus Colletotruchum sp. HK-08 originated from leaves of Nerium indicum.

Objective: To study secondary metabolites from endophytic fungus Colletotruchum sp. HK-08 originated from the leaves of Nerium indicum. Methods: The compounds were isolated by various column chromatographic techniques, and their structures were elucidated by spectroscopic techniques [high resolution electrospray ionization mass spectroscopy (HRESIMS), one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance spectroscopy (NMR)], as well as comparison with literature data. The Ellman method was used to determine the acetylcholinesterase (AChE) inhibitory activity. Results: Four indole derivatives were identified from Colletotruchum sp. HK-08, including 6'-hydroxymonaspiloindole (1), 2-(2-oxoindolin-3-yl)ethyl 2-(4-hydroxyphenyl) acetate (2), 2-(2-oxoindolin-3-yl)ethyl 2-(2-hydroxyphenyl)acetate (3), and monaspiloindole (4). Compound 4 presented weak AChE inhibitory activity with IC50 value of (69.30 ± 6.27) µmol/L [tacrine as the positive control, with IC50 value of (0.61 ± 0.07) µmol/L]. Conclusion: Compounds 1-3 were new compounds, and compound 4 had weak AChE inhibitory activity.

Assessment of bioremediation potential of Calotropis procera and Nerium oleander for sustainable management of vehicular released metals in roadside soils.

Land transportation is a major source of heavy metal contamination along the roadside, posing significant risks to human health through inhalation, oral ingestion, and dermal contact. Therefore, this study has been designed to determine the concentrations of vehicular released heavy metals (Cd, Pb, Ni, and Cu) in roadside soil and leaves of two commonly growing native plant species (Calotropis procera and Nerium oleander).Two busy roads i.e., Lahore-Okara road (N-5) and Okara-Faisalabad roads (OFR) in Punjab, Pakistan, were selected for the study. The data were collected from five sites along each road during four seasons. Control samples were collected ~ 50 m away from road. The metal content i.e. lead (Pb), cadmium (Cd) nickel (Ni) and copper (Cu) were determined in the plant leaves and soil by using Atomic Absorption Spectrophotometer (AAS). Significantly high amount of all studied heavy metals were observed in soil and plant leaves along both roads in contrast to control ones. The mean concentration of metals in soil ranged as Cd (2.20-6.83 mg/kg), Pb (4.53-15.29 mg/kg), Ni (29.78-101.26 mg/kg), and Cu (61.68-138.46 mg/kg) and in plant leaves Cd (0.093-0.53 mg/kg), Pb (4.31-16.34 mg/kg), Ni (4.13-16.34 mg/kg) and Cu (2.98-32.74 mg/kg). Among roads, higher metal contamination was noted along N-5 road. Significant temporal variations were also noted in metal contamination along both roads. The order of metal contamination in soil and plant leaves in different seasons was summer > autumn > spring > winter. Furthermore, the metal accumulation potential of Calotropis procera was higher than that of Nerium oleander. Therefore, for sustainable management of metal contamination, the plantation of Calotropis procera is recommended along roadsides.

Ethnobotanical study of medicinal plants used for cancer treatment at the province of Nador, Morocco

Morocco has varied wealth of aromatic and medicinal plants (AMPs) which are commonly used for prevention and treatment of vario us diseases or as complementary therapy such for cancer diseases. An ethnobotanical study was carried out in the province of Nador, located northeast of Morocco. A total of 418 persons were interviewed, information about their profile, type of medicinal pl ants existing in this area, plant characteristics and uses of those existing plants. Results showed 35 species distributed in 23 families, the most represented were Lamiaceae (7), Apiaceae (5) and Fabaceae (3). This study revealed that the population mainl y used seeds (28%), leaves (26%), aerial parts (20%) and fruits (14%). Moreover, it has shown that Nerium oleander were used by the local population for cancer treatments. Biological activity of N. oleander showed an antimicrobial effect on Escherichia col i , Pseudomonas aeruginosa and Staphylococcus aureus

Marruecos tiene una riqueza vegetal muy variada de plantas aromáticas y medicinales (AMP) y se utilizan com únmente para la prevención y el tratamiento de diversas enfermedades o como terapia complementaria, como las enfermedades del cáncer. Se llevó a cabo un estudio etnobotánico en la provincia de Nador, situada al noreste de Marruecos. Se entrevistó a un tota l de 418 personas, información sobre su perfil, tipo de plantas medicinales existentes en esta zona, características de las plantas, usos de las plantas existentes, etc. Los resultados mostraron una alta riqueza de especies de 35 especies distribuidas en 2 3 familias, las más representadas fueron Lamiaceae (7), Apiaceae (5) y Fabaceae (3). Este estudio reveló que la población utilizó preferentemente semillas (28%), hojas (26%), partes aéreas (20%) y frutos (14%). Además, se ha demostrado que la población loc al utilizaba Nerium oleander para tratamientos contra el cáncer. La actividad biológica de N. oleander mostró un efecto antimicrobiano sobre Escherichia coli , Pseudomonas aeruginosa y Staphylococcus aureus

Poisoning by Nerium oleander L. in Franconia Geese.

This study describes the acute poisoning of four 3-month-old Franconia geese (Anser anser) by oleander plants (Nerium oleander). After the accidental ingestion of oleander clippings, the geese exhibited a rapid onset of severe symptoms, leading to mortality within 15-90 min. Necropsy revealed cardiac and renal lesions. Specifically, interstitial edema, red blood cell infiltration, and myofibril loss were observed in the cardiac muscle, and tubular epithelial degeneration, interstitial edema, and hemorrhages were evident in the kidneys. Oleandrin, a glycoside with cardiac effects, was detected in the liver, kidneys, heart, brain, and muscles. The clinical implications underscore the urgency of veterinary intervention upon oleander ingestion, and the specific findings contribute valuable insights into the pathological effects of acute oleander poisoning in geese, aiding veterinarians in prompt diagnosis and treatment.

Protective efficacy of Nerium oleander extract on spermatogenesis in streptozotocin-induced diabetic rats.

Men with diabetes frequently experience spermatogenic dysfunction, which is the most significant sign that diabetes has harmed their ability to reproduce. The effect of various doses of the hydro-alcoholic extract of Nerium oleander leaves on the pituitary-gonadal axis, sperm motility and number, antioxidant system, changes in testicular tissue structure, and spermatogenesis in healthy and diabetic rats has been examined in the current study. Eighty male rats that had been streptozotocin-induced diabetic and healthy were divided into eight groups: (1) control, (2) Nerium (50 mg/kg), (3) Nerium (100 mg/kg), (4) Nerium (200 mg/kg), (5) DM (6) DM+Nerium (50 mg/kg), (7) DM+Nerium (100 mg/kg) and (8) DM+Nerium (200 mg/kg) and were administered orally for 48 days consecutive. Following the studies, analysis of the testicular tissues' antioxidant capacity as well as sperm parameters, Johnsen's scoring and morphometric evaluation, histology, biochemical and stereology studies were performed.The outcomes showed that Nerium 50 and 100 mg/kg considerably enhanced the testicular morphology, sperm parameters, and reproductive organs to varying degrees in diabetic rats. After Nerium 50 mg/kg administration, glutathione peroxidase (GPX) and catalase (CAT) levels in the testicular tissue were increased whereas malondialdehyde (MDA) levels were markedly decreased. Nerium may help protect against diabetic-induced spermatogenic dysfunction in male rats by enhancing the activities of antioxidant enzymes in lower dosages.

Oleander attenuates hepatic inflammation in a TLR4-independent manner and by favorable modulation of hepatocellular global metabolome that supports cytoprotection.

ETHNOPHARMACOLOGICAL RELEVANCE: Nerium oleander is used to treat liver-associated chronic metabolic diseases in traditional medicinal systems across the globe. The hepatoprotective effects of oleander are mentioned in Indian and Chinese traditional medicinal literature. AIM OF THE STUDY: The present study aimed to investigate the cellular mechanisms behind the hepatoprotective effects of a non-toxic dose of oleander (NO). MATERIALS AND METHODS: The hepatoprotective effects of NO were tested against lipopolysaccharide (LPS)-treated HepG2 cells. Oxidative stress response was studied using cellular enzymatic assays, and gene expression was analyzed using qRT-PCR. HepG2 cells were pretreated with TAK-242 (pharmacological inhibitor of TLR4) to decipher the anti-inflammatory mechanisms of NO. Cell-free metabolites were analyzed using GCMS and were subjected to pathway enrichment analysis. RESULTS: NO reduced systemic inflammation, serum lipid peroxidation byproducts, and glucose without affecting serum transaminase levels and hepatic histopathological features. NO attenuated the inflammation-induced loss of antioxidant enzyme activities and mRNA expressions of toll-like receptor-4 (TLR4)/nuclear factor κß (NFκß)-dependent inflammatory genes. In TAK-242 pretreated cells, LPS was unable to induce inflammatory and oxidative responses. However, NO treatment in TAK-242 pretreated cells with LPS stimulation further reduced the signs of inflammation and improved hepatoprotective activities. A comparative analysis of the intracellular global metabolome from HepG2 cells with and without NO treatment indicated NO-mediated favorable modulation of intracellular metabolic pathways that support cytoprotective activities. CONCLUSION: NO protects HepG2 cells from LPS-induced oxidative and inflammatory injury. The hepatoprotective effects of NO are mediated by a TLR4-independent process and through a favorable modulation of the intracellular global metabolome that supports cytoprotection.

Toxic Garden and Landscaping Plants.

Many popular ornamental shrubs are not only beautiful but also toxic when ingested in sufficient quantities. Common toxic landscaping shrubs in North America include yew (Taxus spp), oleander (Nerium oleander), and rhododendrons and azaleas (Rhododendron spp). Horses are often exposed when plant trimmings are placed within reach or discarded in pastures. Occasionally clippings or fallen leaves contaminate hay. Some plants are unpalatable unless dried and mixed with hay or lawn clippings but others are ingested more readily. In many cases, disease can be severe and treatment unrewarding; therefore, client education is critical to preventing serious and potentially fatal poisonings.

Accidental fatal poisoning in a child due to ingestion of Nerium oleander leaf.

Nerium oleander is an ornamental plant that belongs to the family Apocynaceae. It contains a cardiac glycoside named oleandrin, which is present in all parts of the oleander plant. Suicidal and medication-related deaths due to Nerium oleander poisoning are not uncommon. However, accidental deaths due to oleander leaf ingestion are most commonly encountered. We are reporting a case of an accidental ingestion of Nerium oleander leaf in a child by mistaking it for a guava leaf. The child presented to the casualty with vomiting, poor sensorium, hypotension, and shock. The child developed hyperkalemia, acute kidney injury, myocardial dysfunction, and bleeding manifestations. The urine output was decreased (< 0.5 ml/kg/h). Later, the child died after 36 h. On autopsy examination, periorbital puffiness and bluish discoloration of the nail beds were present. Petechial hemorrhages were present in the heart, kidney, and mesentery. The stomach mucosa was hemorrhagic. Histopathologically, the lung showed interstitial congestion, the liver showed centrilobular necrosis, and the kidney showed acute tubular necrosis. Toxicology analysis was positive for oleander poisoning. This case highlights the toxic nature of Nerium oleander ingestion and the importance of avoiding such plants around residential areas.

Laurel but Hardy: unintended poisoning, a case report of oleander misidentification as bay laurel.

Introduction: Nerium oleander is a toxic plant containing cardiac glycosides throughout all its parts, thereby posing severe health risks upon ingestion. The clinical manifestations of oleander poisoning closely resemble those of digoxin toxicity, encompassing a spectrum of gastrointestinal symptoms, neuropsychiatric disorders, and cardiac disturbances. This scientific case report describes a case of accidental intoxication resulting from the consumption of an oleander leaves infusion misidentified as bay laurel leaves. Case report: An 84-year-old patient consumed an oleander leaves infusion, and after four hours experienced gastrointestinal symptoms. He contacted the poison control center (PCC) and was advised to go to the emergency department (ED). Upon arrival, the patient presented stable vital signs without cardiac irregularities. The PCC recommended the administration of activated charcoal, vigilant monitoring, including electrocardiography (ECG). Subsequent ECGs assessments revealed the presence of third-degree atrioventricular block; in consultation with the PCC, digoxin-specific antibodies and external pacing were necessary. The patient was discharged on the eighth day in good hemodynamic condition, and outpatient follow-up visits showed clinical stability. Discussion: This study offers insights for the management of similar cases. The limitations of conventional assays in measuring oleander cardiac glycosides were observed, emphasizing reliance on clinical evaluation. The patient's trajectory, remaining asymptomatic despite severe ECG changes post-ingestion, underscores the importance of prolonged clinical monitoring.

Differential Activities of the Botanical Extract PBI-05204 and Oleandrin on Innate Immune Functions under Viral Challenge Versus Inflammatory Culture Conditions.

The Nerium oleander extract PBI 05204 (PBI) and its cardiac glycoside constituent oleandrin have direct anti-viral properties. Their effect on the immune system, however, is largely unknown. We used an in vitro model of human peripheral blood mononuclear cells to document effects under three different culture conditions: normal, challenged with the viral mimetic polyinosinic:polycytidylic acid Poly I:C, and inflamed by lipopolysaccharide (LPS). Cells were evaluated for immune activation marks CD69, CD25, and CD107a, and culture supernatants were tested for cytokines. Both PBI and oleandrin directly activated Natural Killer (NK) cells and monocytes and triggered increased production of cytokines. Under viral mimetic challenge, PBI and oleandrin enhanced the Poly I:C-mediated immune activation of monocytes and NK cells and enhanced production of IFN-γ. Under inflammatory conditions, many cytokines were controlled at similar levels as in cultures treated with PBI and oleandrin without inflammation. PBI triggered higher levels of some cytokines than oleandrin. Both products increased T cell cytotoxic attack on malignant target cells, strongest by PBI. The results show that PBI and oleandrin directly activate innate immune cells, enhance anti-viral immune responses through NK cell activation and IFN-γ levels, and modulate immune responses under inflamed conditions. The potential clinical impact of these activities is discussed.

Exploring of the ameliorative effects of Nerium (Nerium oleander L.) ethanolic flower extract in streptozotocin induced diabetic rats via biochemical, histological and molecular aspects.

BACKGROUND: Nerium oleander L. is ethnopharmacologically used for diabetes. Our aim was to investigate the ameliorative effects of ethanolic Nerium flower extract (NFE) in STZ-induced diabetic rats. METHODS: Seven random groups including control group, NFE group (50 mg/kg), diabetic group, glibenclamide group and NFE treated groups (25 mg/kg, 75 mg/kg, and 225 mg/kg) were composed of forty-nine rats. Blood glucose level, glycated hemoglobin (HbA1c), insulin level, liver damage parameters and lipid profile parameters were investigated. Antioxidant defense system enzyme activities and reduced glutathione (GSH) and malondialdehyde (MDA) contents and immunotoxic and neurotoxic parameters were determined in liver tissue. Additionally, the ameliorative effects of NFE were histopathologically examined in liver. mRNA levels of SLC2A2 gene encoding glucose transporter 2 protein were measured by quantitative real time PCR. RESULTS: NFE caused decrease in glucose level and HbA1c and increase in insulin and C-peptide levels. Additionally, NFE improved liver damage biomarkers and lipid profile parameters in serum. Moreover, lipid peroxidation was prevented and antioxidant enzyme activities in liver were regulated by NFE treatment. Furthermore, anti-immunotoxic and anti-neurotoxic effects of NFE were determined in liver tissue of diabetic rats. Histopathogically, significant liver damages were observed in the diabetic rats. Histopathological changes were decreased partially in the 225 mg/kg NFE treated group. SLC2A2 gene expression in liver of diabetic rats significantly reduced compared to healthy rats and NFE treatment (25 mg/kg) caused increase in gene expression. CONCLUSION: Flower extract of Nerium plant may have an antidiabetic potential due to its high phytochemical content.

Biliary parascarosis in a foal.

Migration of Ascaris lumbricoides through the papilla of Vater in humans, and entry into the biliary tree, is well-recognised. Ascaris suum and Toxocara vitulorum have been recovered from the liver of swine and buffalo. We necropsied a Persian Kurdish filly at age 6 months, weighing ∼100 kg. Death evidently was caused by oleander (Nerium oleander) intoxication. An 8-cm adult male Parascaris was found at the lobar-left hepatic bile duct junction. We suggest that the nematode entered anteriorly into the hepatic tree, via the duodenum, major duodenal papilla, bile duct, left hepatic duct and finally the lobar duct. Considering the brief 4-h elapsed time between death and necropsy, and the 18-cm distance from the major duodenal papilla to the location of the parasite, we conclude that entry into the biliary tree likely occurred ante-mortem. We advise consideration of Parascaris infection in differential diagnosis of equine hepatic and pancreatic dysfunction.

A toxic shrub turned therapeutic: The dichotomy of Nerium oleander bioactivities.

Nerium oleander L. is a medicinal plant, used for the treatment of cancers and hyperglycemia across the world, especially in Indian sub-continent, Turkey, Morocco, and China. Although clinical studies supporting its pharmacological effects remain critically underexplored, accidental and intentional consumption of any part of the plant causes fatal toxicity in animals and humans. While the polyphenolic fraction of oleander leaves has been attributed to its pre-clinical pharmacological activities, the presence of diverse cardiac glycosides (especially oleandrin) causes apoptosis to cancer cells in vitro and results in clinical signs of oleander poisoning. Thus, the dual pharmacological and toxicological role of oleander is a perplexing dichotomy in phytotherapy. The current investigative review, therefore, intended to analyze the intrinsic and extrinsic factors that likely contribute to this conundrum. Especially by focusing on gut microbial diversity, abundance, and metabolic functions, oleander-associated pharmacological and toxicological studies have been critically analyzed to define the dual effects of oleander. Electronic databases were extensively screened for relevant research articles (including pre-clinical and clinical) related to oleander bioactivities and toxicity. Taxonomic preference was given to the plant N. oleander L. and synonymous plants as per 'The World Flora Online' database (WCSP record #135196). Discussion on yellow oleander (Cascabela thevetia (L.) Lippold) has intentionally been avoided since it is a different plant. The review indicates that the gut microbiota likely plays a key role in differentially modulating the pharmacological and toxicological effects of oleander. Other factors identified influencing the oleander bioactivities include dose and mode of treatment, cardiac glycoside pharmacokinetics, host-endogenous glycosides, plant material processing and phytochemical extraction methods, plant genotypic variations, environmental effects on the phytochemical quality and quantity, gene expression variations, host dietary patterns and co-morbidity, etc. The arguments proposed are also relevant to other medicinal plants containing toxic cardiac glycosides.

Detection of Highly Poisonous Nerium oleander Using Quantitative Real-Time PCR with Specific Primers.

Nerium oleander is one of the most poisonous plants, and its accidental ingestion has frequently occurred in humans and livestock. It is vital to develop a rapid and accurate identification method for the timely rescue of oleander-poisoned patients and the investigation of poisoning cases. In this study, a specific and highly sensitive quantitative real-time PCR (qPCR)-based method was developed to identify oleander in mixture systems and simulated forensic specimens (SFS). First, a new pair of oleander-specific primers, JZT-BF/BR, was designed and validated. Then, a qPCR method was developed using the primers, and its detective sensitivity was examined. The results showed that JZT-BF/BR could specifically identify oleander in forage and food mixtures, and qPCR was capable of accurate authentication even at a low DNA concentration of 0.001 ng/µL. This method was further applied to the analysis of SFS containing different ratios of N. oleander. The method was confirmed to be applicable to digested samples, and the detection limit reached 0.1% (w/w) oleander in mixture systems. Thus, this study undoubtedly provides strong support for the detection of highly toxic oleander and the diagnosis of food poisoning in humans and animals.

Comparison of Phytoremediation Potential of Nerium indicum with Inorganic Modifier Calcium Carbonate and Organic Modifier Mushroom Residue to Lead-Zinc Tailings.

At present, the application of phytoremediation technology in the ecological remediation of heavy metal tailings is receiving more and more attention. In this study, the physiological and biochemical response and tolerance mechanism of woody plant Nerium indicum to Pb and Zn under different proportions of inorganic modifier calcium carbonate (C1: 5%, C2: 10%, C3: 15%) and organic modifier mushroom residue (M1: 10%, M2: 20%, M3: 30%) was compared. The results showed that the pH value has a trend of C group > M group > CK group and organic matter has a trend of M group > CK group > C group. Phosphatase activity and catalase activity has a trend of M group > C group > CK group, but catalase was more vulnerable to the calcium carbonate concentration. Both modifiers can promote the transformation of Pb, Zn, Cu, and Cd in tailings to more stable organic bound and residual states. However, the stabilization effect of mushroom residue is better, and its stability is Pb, Zn > Cd, Cu. Both modifiers can increase the biomass of Nerium indicum and the modification effect of mushroom residue is better than calcium carbonate. Pb/Zn content and accumulation in Nerium indicum organs showed root > stem > leaf in all groups. Compared with the CK group, the enrichment coefficient of Pb/Zn in C1 and M1 groups decreased, while the translocation factor of Pb/Zn in C1 and M1 groups increased. With the increase in modifier concentration, the enrichment coefficient increases about 1.75~52.94%, but the translocation factor decreases rapidly (20.01~64.46%). Clearly, both the calcium carbonate and mushroom residue amendment could promote the growth ability of Nerium indicum in lead−zinc tailings and strengthen the phytoremediation potential.

Combined transcriptome and metabolome analysis of Nerium indicum L. elaborates the key pathways that are activated in response to witches' broom disease.

BACKGROUND: Nerium indicum Mill. is an ornamental plant that is found in parks, riversides, lakesides, and scenic areas in China and other parts of the world. Our recent survey indicated the prevalence of witches' broom disease (WBD) in Guangdong, China. To find out the possible defense strategies against WBD, we performed a MiSeq based ITS sequencing to identify the possible casual organism, then did a de novo transcriptome sequencing and metabolome profiling in the phloem and stem tip of N. indicum plants suffering from WBD compared to healthy ones. RESULTS: The survey showed that Wengyuen county and Zengcheng district had the highest disease incidence rates. The most prevalent microbial species in the diseased tissues was Cophinforma mamane. The transcriptome sequencing resulted in the identification of 191,224 unigenes of which 142,396 could be annotated. There were 19,031 and 13,284 differentially expressed genes (DEGs) between diseased phloem (NOWP) and healthy phloem (NOHP), and diseased stem (NOWS) and healthy stem (NOHS), respectively. The DEGs were enriched in MAPK-signaling (plant), plant-pathogen interaction, plant-hormone signal transduction, phenylpropanoid and flavonoid biosynthesis, linoleic acid and α-linoleic acid metabolism pathways. Particularly, we found that N. indicum plants activated the phytohormone signaling, MAPK-signaling cascade, defense related proteins, and the biosynthesis of phenylpropanoids and flavonoids as defense responses to the pathogenic infection. The metabolome profiling identified 586 metabolites of which 386 and 324 metabolites were differentially accumulated in NOHP vs NOWP and NOHS and NOWS, respectively. The differential accumulation of metabolites related to phytohormone signaling, linoleic acid metabolism, phenylpropanoid and flavonoid biosynthesis, nicotinate and nicotinamide metabolism, and citrate cycle was observed, indicating the role of these pathways in defense responses against the pathogenic infection. CONCLUSION: Our results showed that Guangdong province has a high incidence of WBD in most of the surveyed areas. C. mamane is suspected to be the causing pathogen of WBD in N. indicum. N. indicum initiated the MAPK-signaling cascade and phytohormone signaling, leading to the activation of pathogen-associated molecular patterns and hypersensitive response. Furthermore, N. indicum accumulated high concentrations of phenolic acids, coumarins and lignans, and flavonoids under WBD. These results provide scientific tools for the formulation of control strategies of WBD in N. indicum.

Antitumor effects of oleandrin in different types of cancers: Systematic review.

Oleandrin, a cardiac glycoside isolated from the leaves of Nerium oleander, has known effects on the heart. Evidence from recent studies have highlighted its potential for anticancer properties. Therefore, we aimed to investigate the effects of oleandrin on cancer cell proliferation, viability and apoptosis in vitro and in vivo. We performed a systematic search in six electronic databases up to Jan 2022. We extracted information about the effects of oleandrin on cell proliferation, cell viability, apoptosis and/or cell cycle arrest in in vitro studies, and the effects on tumor size and volume in animal experimental models. We have retrieved 775 scientific studies. 14 studies met the inclusion criteria. They investigated the effects of oleandrin on breast, lung, pancreatic, colon, prostate, colorectal, oral, ovarian, glioma, melanoma, glioblastoma, osteosarcoma, and histiocytic lymphoma cancers. Overall, in vitro studies demonstrated that oleandrin was able to inhibit cell proliferation, decrease cell viability, and induce apoptosis and/or cell cycle arrest. In addition, oleandrin had an effect on reducing mean tumor size and volume in animal studies. Oleandrin, as a cytotoxic agent, demonstrated antitumor effects in different types of cancers, however important clinical limitations remain a concern. These results encourage future studies to verify the applicability of oleandrin in antineoplastic therapeutic protocols human and veterinary medicine, the investigation of antimetastatic properties, as well as the potential increase in patient survival and the decrease of tumor markers.

Efficacy of oleandrin and PBI-05204 against bovine viruses of importance to commercial cattle health.

BACKGROUND: Bovine viral diarrhea virus (BVDV), bovine respiratory syncytial virus (BRSV). and bovine coronavirus (BCV) threaten the productivity of cattle worldwide. Development of therapeutics that can control the spread of these viruses is an unmet need. The present research was designed to explore the in vitro antiviral activity of the Nerium oleander derived cardiac glycoside oleandrin and a defined N. oleander plant extract (PBI-05204) containing oleandrin. METHODS: Madin Darby Bovine Kidney (MDBK) cells, Bovine Turbinate (BT) cells, and Human Rectal Tumor-18 (HRT-18) cells were used as in vitro culture systems for BVDV, BRSV and BCV, respectively. Cytotoxicity was established using serial dilutions of oleandrin or PBI-05204. Noncytotoxic concentrations of each drug were used either prior to or at 12 h and 24 h following virus exposure to corresponding viruses. Infectious virus titers were determined following each treatment. RESULTS: Both oleandrin as well as PBI-05204 demonstrated strong antiviral activity against BVDV, BRSV, and BCV, in a dose-dependent manner, when added prior to or following infection of host cells. Determination of viral loads by PCR demonstrated a concentration dependent decline in virus replication. Importantly, the relative ability of virus produced from treated cultures to infect new host cells was reduced by as much as 10,000-fold at noncytotoxic concentrations of oleandrin or PBI-05204. CONCLUSIONS: The research demonstrates the potency of oleandrin and PBI-05204 to inhibit infectivity of three important enveloped bovine viruses in vitro. These data showing non-toxic concentrations of oleandrin inhibiting infectivity of three bovine viruses support further investigation of in vivo antiviral efficacy.

The why and how of sunken stomata: does the behaviour of encrypted stomata and the leaf cuticle matter?

BACKGROUND: Stomatal pores in many species are separated from the atmosphere by different anatomical obstacles produced by leaf epidermal cells, especially by sunken stomatal crypts, stomatal antechambers and/or hairs (trichomes). The evolutionary driving forces leading to sunken or 'hidden' stomata whose antechambers are filled with hairs or waxy plugs are not fully understood. The available hypothetical explanations are based mainly on mathematical modelling of water and CO2 diffusion through superficial vs. sunken stomata, and studies of comparative autecology. A better understanding of this phenomenon may result from examining the interactions between the leaf cuticle and stomata and from functional comparisons of sunken vs. superficially positioned stomata, especially when transpiration is low, for example at night or during severe drought. SCOPE: I review recent ideas as to why stomata are hidden and test experimentally whether hidden stomata may behave differently from those not covered by epidermal structures and so are coupled more closely to the atmosphere. I also quantify the contribution of stomatal vs. cuticular transpiration at night using four species with sunken stomata and three species with superficial stomata. CONCLUSIONS: Partitioning of leaf conductance in darkness (gtw) into stomatal and cuticular contributions revealed that stomatal conductance dominated gtw across all seven investigated species with antechambers with different degrees of prominence. Hidden stomata contributed, on average, less to gtw (approx. 70 %) than superficial stomata (approx. 80 %) and reduced their contribution dramatically with increasing gtw. In contrast, species with superficial stomata kept their proportion in gtw invariant across a broad range of gtw. Mechanisms behind the specific behaviour of hidden stomata and the multipurpose origin of sunken stomata are discussed.

Terpestacin, a toxin produced by Phoma exigua var. heteromorpha, the causal agent of a severe foliar disease of oleander (Nerium oleander L.).

Since 1987, several cytochalasins were isolated from Phoma exigua var. heteromorpha, the causal agent of foliar blight disease of oleander (Nerium oleander L.), and chemically and biologically characterised. During the purification process of a large-scale production of cytochalasins A and B, necessary to continue the study on their anticancer activity, a metabolite having a different carbon skeleton compared to that of cytochalasans, was isolated. It was identified as terpestacin, a well-known toxic fungal stestertepenoid, isolated for the first time from P. exigua var. heteromorpha, by spectroscopic investigation (essentially 1D and 2D 1H and 13C-NMR and ESI MS) and optical methods in comparison with the literature data. Terpestacin and some its derivatives (including a natural one, fusaproliferin) were prepared and tested for their biological activity. Terpestacin and fusaproliferin had some inhibitory effects on seed germination of Phelipanche ramosa, whereas none of the compounds caused phytotoxic effects on weed leaves.[Formula: see text].