Spermidine supplementation influence on protective enzymes of Apis mellifera (Hymenoptera: Apidae).

Dietary supplementation has been proposed as a sustainable way to improve the health and resilience of honey bees (Apis mellifera, L.), as the decline in their numbers in recent decades has raised scientific, environmental, and economic concerns. Spermidine, a natural polyamine, has been shown to be a promising substance for honey bee supplementation, as its health-promoting effects have been demonstrated in numerous studies and in different organisms. As already shown, supplementation with spermidine at a certain concentration prolonged lifespan, reduced oxidative stress, and increased antioxidative capacity in honey bees. The aim of the present study was to investigate whether spermidine supplementation affects gene expression and/or enzyme activity of antioxidative and detoxification enzymes and immune response markers in honey bee workers. The different gene expression and enzyme activity patterns observed in abdominal and head tissues in response to spermidine supplementation suggest tissue-specific and concentration-dependent effects. In addition, the immune response markers suggest that spermidine has the ability to boost honey bee immunity. The observed changes make a valuable contribution to understanding the molecular mechanisms by which spermidine may exert its beneficial effects on the bee's health and lifespan. These results support the idea of the use of spermidine supplementation to promote bee health and resilience to environmental stressors, emphasizing that the dose must be carefully chosen to achieve a balance between the pro- and antioxidant effects of spermidine.

Assessment of oxidative status, detoxification capacity and immune responsiveness in honey bees with ageing.

The honey bee (Apis mellifera L.), as an eusocial insect species, is an important model organism in research focusing on ageing and longevity, due to prominent seasonal lifespan plasticity within the worker caste (summer and winter worker bees). In this study, we employed a screening approach to evaluate several molecular parameters, providing comprehensive insights into the antioxidative (superoxide dismutase and catalase activity, reduced glutathione and sulfhydryl group content, total antioxidative capacity), detoxifying (glutathione S-transferase and acetylcholinesterase activity), and immune (phenol oxidase and glucose oxidase activity) status, as well as vitellogenin content, in the summer and winter generation of honey bees, across ageing stages and in two body compartments: the whole abdomen and the head. Summer worker bees were collected weekly for six weeks, while winter bees were collected monthly for five months. The results of our study clearly indicate a reduced overall antioxidative capacity of older groups of worker bees from both generations, while the parameters of immune responsiveness mostly contributed to the separation between the two generations based on season rather than age categories. Detoxification ability appeared to be more susceptible to environmental factors. An age-dependent increase in vitellogenin content was recorded in the abdomen, but without seasonal differences. These findings provide an excellent starting point for further investigations into age-related changes, particularly within the context of honey bee sociality.

Genomic diversity and population structure of Carniolan honey bee in its native habitat.

BACKGROUND: Research into the genetic diversity of honey bee (Apis mellifera L.) populations has become increasingly significant in recent decades, primarily due to population declines attributed to human activities and climate change. As a species of great importance, breeding programs that leverage understanding of genomic diversity could offer solutions to mitigate these challenges. The objective of this study was to examine the genomic diversity and population structure of Carniolan honey bees (Apis mellifera carnica) using the Illumina SNP chip on a large honey bee sample collected from Central and South-Eastern European countries. The study also aims to offer recommendations for future breeding programs. RESULTS: Our analysis involved Discriminant Analysis of Principal Components (DAPC), heterozygosity, admixture analysis, fixation indices (FST), Neighbour-Joining tree, gene flow and Isolation-by-distance analysis. DAPC indicated distinct separation between the Carniolan and Italian honey bee (Apis mellifera ligustica) populations, whereas the admixture analysis revealed varying levels of gene flow and genetic admixture within the Carniolan honey bee populations, demonstrating closer relationships between specific geographic regions (confirmed by Isolation-by-distance analysis). Furthermore, the research of heterozygosity, genomic inbreeding, pairwise FST values, and Neighbour-Joining tree provided insights into the patterns of genetic differentiation and similarity among the populations of Carniolan honey bee within its natural habitat. We have observed genetic homogeneity of the Carniolan honey bee population when considered in a broader genetic/geographical context. However, the Carniolan honey bee has sufficient genetic diversity in its geographical home range that needs to be carefully monitored and maintained. CONCLUSIONS: This study provides important insights into the genetic composition, differentiation, and relationships among Carniolan honey bee populations in Central and South-Eastern European countries. The findings are crucial for conservation efforts, breeding programs, and sustainable beekeeping practices. They emphasise the importance of considering genetic factors and population structure in the breeding and management of honey bees. By understanding these genetic relationships, we can develop strategies to preserve genetic diversity, improve breeding outcomes, and ensure the resilience of honey bee populations in the face of environmental changes and challenges. This knowledge can also inform policy makers and stakeholders on best practices to maintain healthy bee populations, which are vital for ecosystem services and agricultural productivity.

Spermidine supplementation in honey bees: Autophagy and epigenetic modifications.

Polyamines (PAs), including putrescine (Put), spermidine (Spd), and spermine (Spm), are essential polycations with wide-ranging roles in cellular functions. PA levels decline with age, making exogenous PA supplementation, particularly Spd, an intriguing prospect. Previous research in honey bees demonstrated that millimolar Spd added to their diet increased lifespan and reinforced oxidative resilience. The present study is aimed to assess the anti-aging effects of spermidine supplementation at concentrations of 0.1 and 1 mM in honey bees, focusing on autophagy and associated epigenetic changes. Results showed a more pronounced effect at the lower Spd concentration, primarily in the abdomen. Spd induced site-specific histone 3 hypoacetylation at sites K18 and 27, hyperacetylation at K9, with no change at K14 in the entire body. Additionally, autophagy-related genes (ATG3, 5, 9, 13) and genes associated with epigenetic changes (HDAC1, HDAC3, SIRT1, KAT2A, KAT6B, P300, DNMT1A, DNMT1B) were upregulated in the abdomens of honey bees. In conclusion, our findings highlight profound epigenetic changes and autophagy promotion due to spermidine supplementation, contributing to increased honey bee longevity. Further research is needed to fully understand the precise mechanisms and the interplay between epigenetic alterations and autophagy in honey bees, underscoring the significance of autophagy as a geroprotective mechanism.

Spermidine dietary supplementation and polyamines level in reference to survival and lifespan of honey bees.

Honey bee health has been an important and ongoing topic in recent years. Honey bee is also an important model organism for aging studies. Polyamines, putrescine, spermidine and spermine, are ubiquitous polycations, involved in a wide range of cellular processes such as cell growth, gene regulation, immunity, and regulation of lifespan. Spermidine, named longevity elixir, has been most analysed in the context of aging. One of the several proposed mechanisms behind spermidine actions is antioxidative activity. In present study we showed that dietary spermidine supplementation: (a) improved survival, (b) increased the average lifespan, (c) influenced the content of endogenous polyamines by increasing the level of putrescine and spermidine and decreasing the level of spermine, (d) reduced oxidative stress (MDA level), (e) increased the antioxidant capacity of the organism (FRAP), (f) increased relative gene expression of five genes involved in polyamine metabolism, and (g) upregulated vitellogenin gene in honey bees. To our knowledge, this is the first study on honey bee polyamine levels in reference to their longevity. These results provide important information on possible strategies for improving honey bee health by introducing spermidine into their diet. Here, we offer spermidine concentrations that could be considered for that purpose.

Welfare Assessment on Different-Sized Dairy Goat Farms in the Northern Serbian Province of Vojvodina.

This research aimed for the first time to identify the essential welfare problems on 46 goat dairy farms in Vojvodina,based on the goat AWIN welfare protocol. The study showed that space allowance per goat was 1.55, 1.86 and 2.50 m2/goat (large, medium, small-sized farms, respectively). Most farms possessed the soil floor and straw as a flooring material. The small and medium farms more allowed access to the outdoor area. Contrary, large-sized farms mostly kept goats in fully housed systems with reduced opportunities for the goats to express their natural behavior. Management procedures were significantly different (p < 0.05) between the investigated farms. Differences were mainly in bedding, feeding and culling strategies. Low productivity was the main cause of culling in all farm types. Small-sized farms carried out more often disbudding (42.9%) in comparison with medium (21.4%) and large-sized ones (14.3%). Group level observation showed that the main areas of concern were associated with hair coat condition and kneeling at the feeding rack (p < 0.05). Inadequate BCS, udder asymmetry and claw overgrowth were frequently recorded. The prevalence of thin and fat goats was highest in large-sized farms All farm size categories and management systems showed certain welfare weaknesses. Thus, the findings highlighted the need for higher implementation of animal welfare principles and improvement of management techniques to meet the welfare requirements of dairy goats.

Ex Vivo Effect of Ibogaine on the Transcriptional Level of Antioxidant Defense Related Genes in Honey Bee (Apis mellifera, L.) Midgut

Abstract The aim of the present study was to analyze the mechanisms of ibogaine action by measuring its ex vivo effects on antioxidant defense in the honey bee (Apis mellifera, L.) midgut. The transcriptional levels of selected genes: Cu/Zn dependent and Mn dependent superoxide dismutases (Sod1 and Sod2, respectively), catalase (Cat) and transcription factor Nrf2 (Nrf2) were determined. The applicability of midgut tissue, which expected to have well developed antioxidant protection system, for this type of analysis was confirmed by testing cell viability and response to paraquat, an effective inducer of oxidative stress, ex vivo. Incubation for 2 h with paraquat (10 µg/mL) induced a significant increase in expression of Sod1 and Cat genes. The results of ibogaine treatment showed that exposure to 5 µg/mL and 10 µg/mL of ibogaine for 2 h induced significant increase in expression of Sod1 gene. On the other hand, ibogaine did not lead to a significant increase of Sod2, Cat and transcription factor Nrf2 genes expression in honey bee midgut ex vivo. Our results confirmed positive effect of ibogaine on the antioxidant protective system and its pro-antioxidant action.

Effect of fullerenol nanoparticles on oxidative stress induced by paraquat in honey bees.

The enormous progress in nanomaterials development and their use, followed by their inevitable environmental print, has arisen the emerging questions concerning their influence to the living systems. Honey bees are considered to be quite a suitable model system for the risk assessment and prediction of various external influences. To the best of our knowledge, this is the first study dealing with the influence of fullerenol nanoparticles (FNP), a biodegradable carbon nanomaterials' representative, to honey bees. This investigation was conducted with an aim to merge two different open-ended questions: the potential toxic effect of FNP to the bees on the one hand and antioxidative effect of FNP on the other hand. Since FNP antioxidative properties were proved in a number of in vivo models, we hypothesized the similar outcomes, and according to this assumption, we opted for paraquat as a well-known oxidative stress inducer. FNP did not have toxic effect in none of investigated concentrations. The results also confirmed the potential of FNP to reduce oxidative stress through the gene expression of antioxidative enzymes and the change in the redox state of the cells. Additional experiments are needed for a better understanding of the exact mechanism and complex patterns of FNP's activity.

Genetic differentiation between the Old and New types of Serbian Tsigai sheep.

Two Tsigai sheep populations exist in Serbia: the Old type, called Cokan, and the New type. It is assumed that the New type results from upgrading Tsigai sheep with exotic genetic material. We investigated genetic diversity and differentiation of these types by analysing 23 autosomal microsatellites. Tests for Hardy-Weinberg proportions, linkage equilibrium between genotypes across loci and the calculation of inbreeding coefficients were performed and the deficiency in the number of alleles within the Tsigai types was examined using a Wilcoxon sign-rank test. The New type displayed a higher level of genetic variability than the Cokan in terms of allele numbers, but the New Tsigai showed a pattern of heterozygosity deficiency. The positive f value for the Cokan suggests the occurrence of inbreeding in this type. The proportion of linkage disequilibrium was below that expected by chance. Exclusion of two loci in Hardy-Weinberg disequilibrium did not alter our conclusions based on the entire data set i.e. the two Tsigai types are clearly differentiated and the New Tsigai type has been influenced by crossbreeding. Therefore, the Cokan Tsigai should be considered as a distinct endangered breed in the FAO classification.