Exploring marine toxins: comparative analysis of chemical reactivity properties and potential for drug discovery

Marine toxins, produced by various marine microorganisms, pose significant risks to both marine ecosystems and human health. Understanding their diverse structures and properties is crucial for effective mitigation and exploration of their potential as therapeutic agents. This study presents a comparative analysis of two hydrophilic and two lipophilic marine toxins, examining their reactivity properties and bioavailability scores. By investigating similarities among these structurally diverse toxins, valuable insights into their potential as precursors for novel drug development can be gained. The exploration of lipophilic and hydrophilic properties in drug design is essential due to their distinct implications on drug distribution, elimination, and target interaction. By elucidating shared molecular properties among toxins, this research aims to identify patterns and trends that may guide future drug discovery efforts and contribute to the field of molecular toxinology. The findings from this study have the potential to expand knowledge on toxins, facilitate a deeper understanding of their bioactivities, and unlock new therapeutic possibilities to address unmet biomedical needs. The results showcased similarities among the studied systems, while also highlighting the exceptional attributes of Domoic Acid (DA) in terms of its interaction capabilities and stability

Stressors due to handling impair gut immunity in meagre (Argyrosomus regius): the compensatory role of dietary L-Tryptophan

In the context of intensive aquaculture, meagre (Argyrosomus regius) is one of the most important new aquaculture species in Southern Europe and several studies are focused on the optimization of its culture. Nevertheless, stressors such as handling during transport or culture maintenance may affect the immune system, thereby impairing some immune responses or provoking cellular damage. One strategy that has been used to avert this type of negative stress response is the supplementation of amino acids to improve resistance to stress. In this experiment, meagre (105.0 ± 2.6 g, mean ± standard deviation) juveniles were fed two diets for a period of 7 days, the first a commercial diet supplemented with 1% tryptophan (Trp) and second, the same commercial diet without tryptophan supplementation (control group). The effects of two types of handling stressors (air exposure and confinement/netting) on fish fed both diets was evaluated in terms of gene expression of the selected gut immunity markers, such as (1) innate immune response processes: c3 complement (c3), lysozyme (lys), and cyclooxygenase (cox2); (2) humoral immune response processes: interferon type 1 (ifn1), mx protein (mxp), interleukin 1b (il-1b), tumor necrosis factor 1a (tnf1a), and interleukin 10 (il-10); (3) antimicrobial peptides: defensin (def), hepcidin (hep), piscidin (pis), and a marker for mitochondrial respiration: glyceraldehyde 3-phosphate dehydrogenase (gapdh). Samples of the anterior intestine were collected at 1 and 6 h post-stress (hps). Results showed that in fish fed 1% Trp, the air exposure resulted in an upregulation of gene expression at 6 hps for c3, lys, cox2, ifn1, mxp, il-10 and gapdh, and il-1b and pis. The confinement/netting test for fish fed 1% Trp resulted in an upregulation of c3 and mxp and a downregulation of cox2, ifn1, il-1b, tnf1a, il-10, def, hep, and gapdh at both post-stress times (1 and 6 hps). According to the present study, dietary supplementation with 1% Trp may be considered as a proper nutritional strategy for improving tolerance and/or alleviating acute response to handling stressors.info:eu-repo/semantics/publishedVersio

Crecimiento y supervivencia del camarón Penaeus vannamei con aplicación de actinomicetos probióticos y homeopatía

The effect of probiotic bacteria and homeopathic medicines on growth, survival and water quality in the culture of juveniles of White Pacific shrimp Penaeus vannamei was evaluated. Four experimental groups were treated for 30 days with two probiotic strains of Streptomyces spp. RL8 (T1) and N7 (T2), homeopathic products developed in CIBNOR from pathogenic bacteria [ViP-7C + VIA-7C] (T3), homeopathic medicines for humans [PhA-7C + SIT-7C] (T4) and distilled water as a control group (T5). Shrimp treated with T2, T3 and T4 showed a significantly greater weight gain (P<0,05) compared to the T5 control. The average daily weight gain was significantly higher (P<0,05) in shrimp treated with T2 and T3, compared to T5. With respect to the survival rate, there were significant differences (P<0,05) between the treated groups (T1, T2 and T3) and the control group (T5). The density of Vibrio spp. in the culture water was significantly lower (P<0,05) in T1, T3 and T4 than in T5. With reference to T5, a significant reduction (P<0,05) of vibrios in the hepatopancreas was observed in all experimental groups. As a counterpart, the abundance of total marine heterotrophic bacteria in the hepatopancreas in all experimental groups was significantly higher (P<0.05) compared to the control. These results demonstrate that the application of probiotic actinomycetes and homeopathic medicines has potential as an alternative to the use and abuse of expensive and potentially harmful antibiotics, since in addition to maintaining good water quality they promote growth and survival of P. vannanmei, they are bio-safe and could be economically competitive for application in the commercial cultivation of the species.Se evaluó el efecto de bacterias probióticas y medicamentos homeopáticos sobre el crecimiento, la supervivencia y la calidad del agua en el cultivo de juveniles del camarón blanco del pacífico Penaeus vannamei. Cuatro grupos experimentales fueron tratados durante 30 días con dos cepas probióticas de Streptomyces spp. RL8 (T1) y N7 (T2), con productos homeopáticos desarrollados en CIBNOR a partir de bacterias patógenas [ViP-7C+VIA-7C] (T3), con medicamentos homeopáticos para humanos [PhA-7C+SIT-7C] (T4) y con agua destilada como grupo control (T5). Los camarones tratados con T2, T3 y T4 mostraron una ganancia significativamente mayor en peso (P<0.05) con respecto a T5. El peso diario ganado fue significativamente mayor (P<0,05) en los camarones tratados con T2 y T3, con respecto a T5. Se registraron diferencias significativas (P<0,05) en la tasa de supervivencia de camarones tratados con T1, T2 y T3, con respecto al control (T5). La densidad de Vibrio spp. en el agua de cultivo fue significativamente menor (P<0,05) en T1, T3 y T4, que en T5. Tomando como referencia a T5, en todos los grupos experimentales se observó una reducción significativa (P<0,05) de vibrios en el hepatopáncreas. Como contraparte, la abundancia de bacterias heterótrofas marinas totales en el hepatopáncreas en todos los grupos experimentales fue significativamente mayor (P<0,05) con respecto al control (T5). Estos resultados demuestran que la aplicación de actinomicetos probióticos y de medicamentos homeopáticos tiene potencial como alternativa al uso y abuso de antibióticos costosos y potencialmente nocivos, ya que además de mantener buena calidad del agua promueven el crecimiento y la supervivencia de P. vannanmei, son bio-seguros y podrían ser económicamente competitivos para su aplicación en el cultivo comercial de la especie

Debaryomyces hansenii supplementation in low fish meal diets promotes growth, modulates microbiota and enhances intestinal condition in juvenile marine fish

Background The development of a sustainable business model with social acceptance, makes necessary to develop new strategies to guarantee the growth, health, and well-being of farmed animals. Debaryomyces hansenii is a yeast species that can be used as a probiotic in aquaculture due to its capacity to i) promote cell proliferation and differentiation, ii) have immunostimulatory effects, iii) modulate gut microbiota, and/or iv) enhance the digestive function. To provide inside into the effects of D. hansenii on juveniles of gilthead seabream (Sparus aurata) condition, we integrated the evaluation of the main key performance indicators coupled with the integrative analysis of the intestine condition, through histological and microbiota state, and its transcriptomic profiling. Results After 70 days of a nutritional trial in which a diet with low levels of fishmeal (7%) was supplemented with 1.1% of D. hansenii (17.2 × 105 CFU), an increase of ca. 12% in somatic growth was observed together with an improvement in feed conversion in fish fed a yeast-supplemented diet. In terms of intestinal condition, this probiotic modulated gut microbiota without affecting the intestine cell organization, whereas an increase in the staining intensity of mucins rich in carboxylated and weakly sulphated glycoconjugates coupled with changes in the affinity for certain lectins were noted in goblet cells. Changes in microbiota were characterized by the reduction in abundance of several groups of Proteobacteria, especially those characterized as opportunistic groups. The microarrays-based transcriptomic analysis found 232 differential expressed genes in the anterior-mid intestine of S. aurata, that were mostly related to metabolic, antioxidant, immune, and symbiotic processes. Conclusions Dietary administration of D. hansenii enhanced somatic growth and improved feed efficiency parameters, results that were coupled to an improvement of intestinal condition as histochemical and transcriptomic tools indicated. This probiotic yeast stimulated host-microbiota interactions without altering the intestinal cell organization nor generating dysbiosis, which demonstrated its safety as a feed additive. At the transcriptomic level, D. hansenii promoted metabolic pathways, mainly protein-related, sphingolipid, and thymidylate pathways, in addition to enhance antioxidant-related intestinal mechanisms, and to regulate sentinel immune processes, potentiating the defensive capacity meanwhile maintaining the homeostatic status of the intestine.This work has been financed through the DIETAplus project of JACUMAR (Junta de Cultivos Marinos, MAPAMA; Spanish government), which is co-funded with FEMP funds (EU). Furthermore, this research was funded by means of grants from the Spanish Government: PID2019-106878RB-I00 and IS was granted with a Postdoctoral fellowship (FJC2020-043933-I). EVV and FERL thank the support of Fondecyt iniciación (project number 11221308) and Fondecyt regular (project number 11221308) grants (Agencia Nacional de Investigacióny Desarrollo de Chile, Government of Chile), respectively. Collaboration between Ibero-American researchers has been done under the framework of the network LARVAplus “Strategies for the development and im-provement of fish larvae production in Ibero-America” (117RT0521) funded by the Ibero-American Program of Science and Technology for Development (CYTED, Spain).info:eu-repo/semantics/publishedVersio

Agricultural Homoeopathy: A New Insight into Organics

At present, agricultural homoeopathy is being increasingly implemented worldwide to mitigate the negative effects caused by the indiscriminate use of chemical products in conventional agricultural practices. It is a viable alternative to improve organic agriculture, since homoeopathic medicines are innocuous substances with a capability to activate measurable response mechanisms when used in plants, animals and humans. Experimental research results allow us to conclude in this chapter that agricultural homoeopathy is able to stimulate favourable biological and even genetic responses in plants (basil Ocimum basilicum L., bean Phaseolus vulgaris L., cucumber Cucumis sativus L., tomato Solanum lycopersicum L.), which shows a novelty insight for organic agriculture

Aquacultural Homoeopathy: A Focus on Marine Species

Homoeopathy is an alternative medical system proposed by Samuel Hahnemann in the eighteenth century. It uses highly diluted and agitated substances that derived from plants, minerals or animals, which have shown to be effective in human medicine, agronomy, veterinary, and as a novelty, in marine aquaculture. Aquacultural homoeopathy has developed rapidly in recent years, partially motivated by the misuse of powerful drugs (hormones, antibiotics, disinfectants) that when solving a problem generate undesirable side effects. In the last 10 years, scientific articles have been published on its application in freshwater fish native to Brazil, obtaining beneficial effects on growth, survival, hepatosomatic index, development of muscle fibres and lipid content in muscle. At Centro de Investigaciones Biológicas del Noroeste (CIBNOR, Mexico: www.cibnor.mx), we have studied the effects of homoeopathy to improve the culture of economically important marine species of molluscs, fish and shrimp. In this chapter, we show a selection of different research with preliminary or advanced results, related to the use of homoeopathy and its impact on zootechnic, biochemical, genomic and transcriptomic parameters in marine molluscs, fish and crustaceans. The results obtained suggest that homoeopathy is an eco-friendly alternative applicable in aquaculture industry to improve various productive and health aspects

Estudio de la actividad superóxido y dismutasa y peróxidasa de Microcoleus chthonoplastes (Oscillatoriacea: cianobacteria) CEPA SC7B9002-1 bajo estres oxidativo

Impreso y PD

Toxicogenomic Effects of Dissolved Saxitoxin on the Early Life Stages of the Longfin Yellowtail (<i>Seriola rivoliana</i>)

Harmful algal blooms (HABs) can produce a variety of noxious effects and, in some cases, the massive mortality of wild and farmed marine organisms. Some HAB species produce toxins that are released into seawater or transferred via food webs (particulate toxin fraction). The objective of the present study was to identify the toxicological effects of subacute exposure to saxitoxin (STX) during embryonic and early larval stages in Seriola rivoliana. Eggs were exposed to dissolved 19 STX (100 μg L−1). The toxic effects of STX were evaluated via the hatching percentage, the activity of three enzymes (protein and alkaline phosphatases and peroxidase), and the expression of four genes (HSF2, Nav1.4b, PPRC1, and DUSP8). A low hatching percentage (less than 5%) was observed in 44 hpf (hours post fertilization) embryos exposed to STX compared to 71% in the unexposed control. At this STX concentration, no oxidative stress in the embryos was evident. However, STX induced the expression of the NaV1.4 channel α-subunit (NaV1.4b), which is the primary target of this toxin. Our results revealed the overexpression of all four candidate genes in STX-intoxicated lecithotrophic larvae, reflecting the activation of diverse cellular processes involved in stress responses (HSF2), lipid metabolism (PPRC1), and MAP kinase signaling pathways associated with cell proliferation and differentiation (DUSP8). The effects of STX were more pronounced in young larvae than in embryos, indicating a stage-specific sensitivity to the toxin