Chemistry and biological activities of the marine sponges of the genera mycale (Arenochalina), Biemna and Clathria

Over the past seven decades, particularly since the discovery of the first marine-derived nucleosides, spongothymidine and spongouridine, from the Caribbean sponge Cryptotethya crypta in the early 1950s, marine natural products have emerged as unique, renewable and yet under-investigated pools for discovery of new drug leads with distinct structural features, and myriad interesting biological activities. Marine sponges are the most primitive and simplest multicellular animals, with approximately 8900 known described species, although more than 15,000 species are thought to exist worldwide today. These marine organisms potentially represent the richest pipeline for novel drug leads. Mycale (Arenochalina) and Clathria are recognized marine sponge genera belonging to the order Poecilosclerida, whereas Biemna was more recently reclassified, based on molecular genetics, as a new order Biemnida. Together, these sponge genera contribute to the production of physiologically active molecular entities with diverse structural features and a wide range of medicinal and therapeutic potentialities. In this review, we provide a comprehensive insight and up-to-date literature survey over the period of 1976–2018, focusing on the chemistry of the isolated compounds from members of these three genera, as well as their biological and pharmacological activities, whenever available. © 2018 by the authors.Acknowledgments: This work was supported by the mission sector of the Ministry of High Education of the Arab Republic of Egypt (Egyptian cultural bureau in Paris and Athens); Amr El-Demerdash’s, and Mohamed Tammam’s joint supervision were fully funded and supported

Feeding dihydroquercetin in wheat-based diets to laying hens: impact on egg production and quality of fresh and stored eggs

1. This study assessed the impact of dietary dihydroquercetin (DHQ) in wheat-based diets on egg production, composition and quality when fed to laying hens. A total of 80 Hy-Line Brown hens were allocated to 20 enriched layer cages, over two tiers, in groups of four birds. 2. Two wheat-based diets were used in the study. A basal diet, meeting the nutrient requirement of the hens, containing 11.56 MJ/kg AME and 172 g/kg crude protein, was mixed and split in two parts. One part was fed as prepared to the control group of birds. The second diet was made by adding 1.5 g DHQ per kg basal diet and fed to the treatment group of birds. This level was relatively high and extended the data on levels normally fed. The diets were fed in a meal form and did not contain any coccidiostat, antimicrobial growth promoters or other similar additives. Each diet was fed to hens in 10 replicate cages for four weeks, from 22 to 26 weeks of age, following randomisation. 3. Subsequently, eggs were investigated to determine the impact of dietary DHQ on the quality variables of fresh and 28-day stored eggs. 4. Overall, feeding 1.5 g/kg dietary DHQ for four weeks did not affect (P>0.05) egg production or the quality of fresh and stored eggs. Any observed egg quality changes (P<0.05) confirmed the expected effects of egg storage

Magnetoelectric ordering of BiFeO3 from the perspective of crystal chemistry

In this paper we examine the role of crystal chemistry factors in creating conditions for formation of magnetoelectric ordering in BiFeO3. It is generally accepted that the main reason of the ferroelectric distortion in BiFeO3 is concerned with a stereochemical activity of the Bi lone pair. However, the lone pair is stereochemically active in the paraelectric orthorhombic beta-phase as well. We demonstrate that a crucial role in emerging of phase transitions of the metal-insulator, paraelectric-ferroelectric and magnetic disorder-order types belongs to the change of the degree of the lone pair stereochemical activity - its consecutive increase with the temperature decrease. Using the structural data, we calculated the sign and strength of magnetic couplings in BiFeO3 in the range from 945 C down to 25 C and found the couplings, which undergo the antiferromagnetic-ferromagnetic transition with the temperature decrease and give rise to the antiferromagnetic ordering and its delay in regard to temperature, as compared to the ferroelectric ordering. We discuss the reasons of emerging of the spatially modulated spin structure and its suppression by doping with La3+.Comment: 18 pages, 5 figures, 3 table

Bupleurum chinense Roots: a Bioactivity-Guided Approach toward Saponin-Type NF-κB Inhibitors

The roots of Bupleurum chinense have a long history in traditional medicine to treat infectious diseases and inflammatory disorders. Two major compounds, saikosaponins A and D, were reported to exert potent anti-inflammatory activity by inhibiting NF-κB. In the present study, we isolated new saikosaponin analogues from the roots of B. chinese interfering with NF-κB activity in vitro. The methanol-soluble fraction of the dichloromethane extract of Radix Bupleuri was subjected to activity-guided isolation yielding 18 compounds, including triterpenoids and polyacetylenes. Their structures were determined by spectroscopic methods as saikogenin D (1), prosaikogenin D (2), saikosaponins B2 (3), W (4), B1 (5), Y (6), D (7), A (8), E (9), B4 (10), B3 (11), and T (12), saikodiyne A (13), D (14), E (15) and F (16), falcarindiol (17), and 1-linoleoyl-sn-glycero-3-phosphorylcholine (18). Among them, 4, 15, and 16 are new compounds, whereas 6, previously described as a semi-synthetic compound, is isolated from a natural source for the first time, and 13–17 are the first reports of polyacetylenes from this plant. Nine saponins/triterpenoids were tested for inhibition of NF-κB signaling in a cell-based NF-κB-dependent luciferase reporter gene model in vitro. Five of them (1, 2, 4, 6, and 8) showed strong (&gt; 50%, at 30 µM) NF-κB inhibition, but also varying degrees of cytotoxicity, with compounds 1 and 4 (showing no significant cytotoxicity) presenting IC50 values of 14.0 µM and 14.1 µM in the cell-based assay, respectively

Effect of rearing temperature on physiological measures and antioxidant status of broiler chickens fed stevia (Stevia rebaudiana B.) leaf meal and exogenous xylanase

Background The global climate is warming. Heat stress, as a result of high ambient temperatures, may negatively impact physiology and reduce growth performance of poultry. Stevia is a perennial shrub indigenous to South America where its phytochemical extracts have been used as a natural sweetener for hundreds of years. Its physiological effects, including antioxidant properties, on poultry are well known, however, the translation of these to improved growth performance is variable. Combining stevia with a commercial xylanase to enhance feed digestibility could therefore form a feeding strategy to partially mitigate the negative impact of rearing birds under high ambient temperatures. Purpose The study aimed to compare the growth performance, dietary energy and nutrient availability, oxidative status, gastrointestinal tract development, and caecal short chain fatty acid concentration; at two ambient rearing temperatures, when feeding diets containing stevia and exogenous xylanase, alone or in combination, to broiler chickens. Study design/Methods: Day-old chicks (n = 105) were reared in a single floor pen following breeder recommendations for the first 7 days, whereupon birds (n = 96) were randomly allocated to one of four experimental diets (negative control, stevia at 20 g/kg diet, xylanase at 100 FXU/kg diet, stevia at 20 g/kg diet + xylanase at 100 FXU/kg diet), in one of two environmental conditions (high ambient temperature at 32 ± 2 °C or regular rearing at breeder recommendations), in a 2 × 2 × 2 factorial design. Results Rearing birds at high ambient temperature reduced daily feed intake (p = 0.02). Birds fed stevia and reared at regular temperature had similar weight gain to birds reared in high ambient temperatures, although birds on the control diet housed at regular temperatures had the greatest weight gain (P < 0.05). Exogenous xylanase improved overall dietary metabolisable energy and improved nitrogen retention in the high ambient temperature group only (P < 0.05). Dietary stevia reduced caecal digesta butyric acid: acetic acid at regular temperature, but xylanase increased the butyric acid concentration at high ambient temperature (P < 0.05). Dietary stevia increased (P < 0.001) the hepatic carotenoid concentrations and xylanase improved (P < 0.05) hepatic vitamin E concentrations. Conclusions Rearing temperature is an important environmental factor in broiler production. Exogenous xylanase supplementation can increase feed efficiency and dietary metabolisable energy. Feeding xylanase or stevia improves hepatic antioxidant status in broilers by increasing hepatic vitamin E and carotenoids, respectively, suggesting that either may be effective in counteracting oxidative stress

Second harmonic generation and birefringence of some ternary pnictide semiconductors

A first-principles study of the birefringence and the frequency dependent second harmonic generation (SHG) coefficients of the ternary pnictide semiconductors with formula ABC$_2$ (A = Zn, Cd; B = Si, Ge; C = As, P) with the chalcopyrite structures was carried out. We show that a simple empirical observation that a smaller value of the gap is correlated with larger value of SHG is qualitatively true. However, simple inverse power scaling laws between gaps and SHG were not found. Instead, the real value of the nonlinear response is a result of a very delicate balance between different intraband and interband terms.Comment: 13 pages, 12 figure

Impact of #PsychTwitter in promoting global psychiatry: A hashtag analysis study

Introduction: Multiple studies have shown how valuable Twitter hashtags can be for promoting content related to different themes in the online community. This arena has grown into a rich data source for public health observation and understanding key trends in healthcare on a global scale. In the field of mental health in particular, it would be of benefit to understand and report the key stakeholders' (individual mental health professionals, academic organizations and their countries) trends and patterns of psychiatric knowledge and information dissemination using #PsychTwitter. Objective(s): In this study, we aim to evaluate the achieved outreach of psychiatry-related tweets using the hashtag #PsychTwitter. Method(s): We utilized the Symplur Signals research analytics tool to characterize tweets containing #PsychTwitter from the 20th of August, 2019, to the 20th of August, 2022. Result(s): The #PsychTwitter movement resulted in 125,297 tweets that were shared by 40,058 Twitter users and generated a total of 492,565,230 impressions (views). The three largest identified groups of contributors were Doctors (13.8 of all tweets), Org. Advocacy (6.2 of all tweets), and Researcher/Academic (4 of all tweets) stakeholders. The top influential accounts consisted of 55 psychiatrists and 16 institutional or organizational accounts. The top 5 countries from where most of the tweets containing #PsychTwitter were shared include the United States (54.3 of all users), the United Kingdom (10.4 of all users), Canada (4.9 of all users), India (2 of all users), and Australia (1.8 of all users). Conclusion(s): This is the first of its kind study featuring the influence and usage of #PsychTwitter and covering its global impact in the field of psychiatry using the Twitter platform. Our results indicate that Twitter represents a broadly used platform for mental health-related discussions

Feeding dihydroquercetin and vitamin E to broiler chickens reared at standard and high ambient temperatures

The use of natural antioxidants, in particular polyphenols such as dihydroquercetin (DHQ), in animal nutrition has recently increased in popularity. This may partly be due to the risk of increased incidences of heat stress associated with raising livestock in warmer ambient temperatures, facilitated by global warming, reducing antioxidant capacity. The current research demonstrates the effect of dietary DHQ, vitaminEand standard or high ambient temperatures on growth performance, energy and nutrient metabolism, gastrointestinal tract (GIT) development, jejunal villus morphometry and antioxidant status in broiler chickens. Each of the four experimental diets was fed to 16 pens of five birds, which were allocated to four rooms (four pens in each room). The temperature in two rooms was maintained at aconstant 35°C (high temperature; HT), and the temperature in the other two rooms was gradually reduced from 27°C at 7 dof age to 22°C at 20 dof age (standard temperature; ST). Rearing birds at HT reduced feed intake, weight gain, weight of small intestine, total GIT, liver, spleen, heart, villus height, villus surface area and lowered blood glutationperoxidase (GSH-Px). Dietary DHQ increased blood GSH-Px and total antioxidant status, increased heart weight and reduced caecal size. When fed separately, DHQ and vitamin E improved hepatic vitamin E concentration. Feeding vitamin Eincreased spleen and liver weights. When fed together, DHQ and vitamin Ereduced villus height, villus height to crypt depth ratio and villus surface area. Temperature and antioxidants did not affect energy and nutrient metabolism. There were no effects of dietary antioxidants on growth performance of broiler chickens and there were no mortalities. At present, it is unclear if feeding antioxidants (in particular DHQ) at different levels, using different dietary formulations, and rearing birds under arange of environmental conditions may be effective at enhancing production performance and bird health in hot ambient climates

Polyacetylenes from Notopterygium incisum–New Selective Partial Agonists of Peroxisome Proliferator-Activated Receptor-Gamma

Peroxisome proliferator-activated receptor gamma (PPARγ) is a key regulator of glucose and lipid metabolism and therefore an important pharmacological target to combat metabolic diseases. Since the currently used full PPARγ agonists display serious side effects, identification of novel ligands, particularly partial agonists, is highly relevant. Searching for new active compounds, we investigated extracts of the underground parts of Notopterygium incisum, a medicinal plant used in traditional Chinese medicine, and observed significant PPARγ activation using a PPARγ-driven luciferase reporter model. Activity-guided fractionation of the dichloromethane extract led to the isolation of six polyacetylenes, which displayed properties of selective partial PPARγ agonists in the luciferase reporter model. Since PPARγ activation by this class of compounds has so far not been reported, we have chosen the prototypical polyacetylene falcarindiol for further investigation. The effect of falcarindiol (10 µM) in the luciferase reporter model was blocked upon co-treatment with the PPARγ antagonist T0070907 (1 µM). Falcarindiol bound to the purified human PPARγ receptor with a Ki of 3.07 µM. In silico docking studies suggested a binding mode within the ligand binding site, where hydrogen bonds to Cys285 and Glu295 are predicted to be formed in addition to extensive hydrophobic interactions. Furthermore, falcarindiol further induced 3T3-L1 preadipocyte differentiation and enhanced the insulin-induced glucose uptake in differentiated 3T3-L1 adipocytes confirming effectiveness in cell models with endogenous PPARγ expression. In conclusion, we identified falcarindiol-type polyacetylenes as a novel class of natural partial PPARγ agonists, having potential to be further explored as pharmaceutical leads or dietary supplements

Plant extracts in cell-based anti-inflammatory assays—Pitfalls and considerations related to removal of activity masking bulk components

Plants used in traditional medicine represent an important source of new lead compounds. However, cell-based in vitro screening assays with plant material are hampered by the complex nature of plant extracts as mixtures of active and inactive components. Bulk constituents, such as chlorophyll and polyphenols were previously shown to interfere with several biological in vitro assays. Their influence on anti-inflammatory cell-based testing systems has not been thoroughly investigated. Hence, the present study was aimed at comparing different procedures for the removal of bulk constituents from plant extracts and examining the influence of their elimination on selected cell-based anti-inflammatory assays. Malva sp. and Glechoma hederacea L., two plants used in traditional European medicine for the treatment of inflammatory disorders, were subjected to three different methods for the removal of chlorophyll and polyphenols, respectively. Removal of bulk constituents was confirmed by HPLC and mass spectrometry. Extracts were tested before and after the purification procedure, to determine their potential to inhibit the activation of the transcription factor NF-κB in reporter gene assay and to interfere with the secretion of the chemokine IL-8 after stimulation of endothelial cells with tumor necrosis factor (TNF-α) or lipopolysaccharide (LPS). Removal of chlorophyll from tested extracts led to a strong decrease in the anti-inflammatory activities, due to loss of bioactive constituents. In contrast, the effect of the polyphenol-free extracts was either not changed or significantly increased, depending on the purification method used. The study concluded that clearance of bulk compounds represents a valuable strategy for cell-based in vitro anti-inflammatory evaluation of plant extracts. Liquid–liquid partitioning was identified as the optimal method for the elimination of both chlorophyll and polyphenols. It is recommended that removal of chlorophyll from extracts always be accompanied by HPLC profiling to detect a possible loss of active constituents