Search Results (35)

Worker honey bees are crucial for colony stability and ecosystem pollination. However, the cross-scale aging features and underlying mechanisms in the Eastern honey bee (Apis cerana) remain poorly understood. This study systematically investigated age-related changes in A. cerana workers across youth (1~5 days post-emergence, dpe), middle age (29 dpe), and old age (50 dpe) through integrated morphological, ultrastructural, and transcriptomic analyses. With increasing age, the phenotypic deterioration in the old bees (OBs) was significant: the body color brightness decreased by 16.7% compared to the young bees (YBs) (p < 0.001), and the hair density of the head, thorax, and abdomen declined by 63.5%, 97.2%, and 91.5%, respectively (p < 0.0001). The wing wear index (WWI) increased to 96.7% (p < 0.0001). The locomotor performance declined sharply, with only 6.7% of the OBs successfully reaching the feeding platform within 15 s (p < 0.0001). Ultrastructural analysis revealed sensory organ abrasion, flattened thoracic bristles, thickened cuticle, and 90.4% increased mitochondrial damage (p < 0.0001). The autophagosomes showed dynamic changes, with 81.8% reduction versus those of mid-aged bees (MBs) (p < 0.001), which suggests that mitochondrial dysfunction and autophagy dysregulation may be the core driving factors behind aging. Transcriptomics identified 67 differentially expressed genes enriched in lifespan regulation, glutathione metabolism, and lysosomal pathways. Fifteen key aging-related genes were identified, such as major royal jelly protein 3 (MRJP3), synaptic vesicle glycoprotein 2A (SV2A), and apidermin 3 (APD3), whose expression dynamics have been shown to be closely related to nutritional metabolism, behavioral perception, and the decline of epidermal barrier function. This work establishes the first multidimensional aging evaluation system for A. cerana, providing critical insights into bee senescence mechanisms and colony health optimization. Full article

Royal jelly (RJ), a secretion from nurse bees, is a key factor in honeybee caste differentiation and a high-value product in apitherapy. Despite its economic and biological importance, factors affecting its yield and composition remain insufficient. This study investigated the impact of grafted larval age and sex and the collection day of RJ on its yield and physicochemical characteristics. Three independent experiments were conducted using strong Apis mellifera L. colonies. Larvae of different ages (first, second, and third) were grafted, and RJ was harvested 24, 48, and 72 h post grafting. Additionally, worker and drone larvae were used to assess the effect of larval sex. RJ was analyzed for moisture, protein, sugar, and 10-hydroxy-2-decenoic acid (10-had) content. Results showed that RJ yield significantly increased with collection day, with the third day being optimal. Protein content declined over time, while moisture content rose, although sugar levels and 10-HDA remained stable. Second-day larvae yielded the highest RJ volume without affecting composition. Larval sex did not significantly influence either RJ yield or composition. The results of this study may provide valuable insights into the quality determinants of royal jelly, enabling beekeepers to optimize production for both enhanced royal jelly yield and the rearing of higher-quality queen bees. Full article

10-Hydroxy-2-decenoic acid (10-HDA), a major fatty acid (FA) component of royal jelly, is synthesized in the mandibular glands (MGs) of worker honeybees. Despite its well-documented nutritional and therapeutic significance, the biosynthetic pathway and regulatory mechanisms of 10-HDA production remain largely unresolved. In this study, the molecular basis of 10-HDA biosynthesis and regulation in the MGs of newly emerged bees (NEBs), nurse bees (NBs), and forager bees (FBs) were investigated using RNA sequencing and weighted gene co-expression network analysis (WGCNA). A five-step biosynthetic pathway for 10-HDA was proposed, and cross-species analysis of Apis mellifera and A. cerana revealed the conserved expression patterns of 15 key enzymes involved. Functional validation via RNA interference (RNAi) demonstrated that knockdown of acyl-CoA Delta(11) desaturase (d11ds, LOC551527), a key enzyme in FA desaturation, led to a 50% reduction in 10-HDA levels. Protein–protein interaction (PPI) network analysis further identified transcriptional regulators Kay and Drep-2 as potential modulators of 10-HDA metabolism. This study provides the first comprehensive mechanistic model of 10-HDA biosynthesis in honeybee MGs and highlights the labor-specific regulation of FA metabolism. These findings offer promising genetic targets for improving the royal jelly quality through genetic technology. Full article

Bee products, such as honey, bee pollen/bread, bee propolis and royal jelly foraged or secreted by honeybee workers, have been consumed by humans for many years and are important due to their complexity, the large number of them and the endemicity of their constituents. The health-promoting activities of bee products are widely documented all around the world. However, we have noticed a distinct but poorly described feature of bee products: groups of functionally opposite components (FOCs) related to blood sugar level, oxidative stress, cell membrane cholesterol distribution, cell membrane stability, cell membrane curvature, allergic reaction, cellular sodium influx and cardiac apoptosis that exist within these products. We then propose the Equivalence Index in order to overcome the challenges associated with FOCs; this is a concise mathematical model that can be used to optimize the evaluation of quality, determine any underlying mechanisms and provide processing guidance regarding bee products. Full article

Vincristine (VCR) is a chemotherapeutic agent classified as a vinca alkaloid. Royal jelly (RJ) is a significant bee product produced by worker bees, characterized by its high protein content. This study aims to investigate the protective effects of RJ against VCR-induced liver damage. VCR was intraperitoneally administered at a dose of 0.1 mg/kg body weight (b.w.) and RJ was orally administered at doses of 150 and 300 mg/kg b.w. Both treatments were applied to the rats on days 1–6 and 9–14. The composition of RJ was analyzed using LC-MS/MS, revealing the presence of 15 different phytochemical compounds with strong antioxidant properties. Serum samples obtained from the rats were analyzed for ALT, ALP, and AST levels. While these enzyme levels were significantly elevated in the VCR group, a notable reduction was observed following RJ administration. Additionally, SOD, CAT, GPx, and GSH antioxidant parameters, along with MDA levels, were evaluated in liver tissue samples. The results indicated a decrease in SOD, CAT, GPx, and GSH activities/levels and an increase in MDA levels in the VCR group. Furthermore, ELISA was used to assess JAK2, STAT3, and mTOR/PI3K/AKT signaling pathways. VCR administration led to a decrease in mTOR/PI3K/AKT levels and an increase in JAK2 and STAT3 levels. In addition, the mRNA transcription levels of inflammation (NF-κB, TNF-α, and IL-1β), endoplasmic reticulum (ER) stress (IRE-1, GRP78, PERK, and ATF-6), and autophagy markers (LC3A and LC3B) were examined. A significant increase in inflammation, ER stress, and autophagy-related markers was observed in the VCR-treated group. Lastly, the protein expression levels of Bax, Bcl-2, Caspase-3, and NF-κB were evaluated. VCR treatment increased Bax, Caspase 3, and NF-κB levels, whereas Bcl-2 levels were decreased. However, following RJ administration, all these parameters were reversed, demonstrating significant improvements. In conclusion, these findings suggest that RJ may exert a protective effect against VCR-induced liver damage. Full article

The honey bee Apis cerana cerana (A. c. cerana), a subspecies of Apis cerana, is endemic in China and possesses a valuable ecological niche. Understanding the ways to protect this honey bee’s populations is crucial, but this topic has been understudied. For the efficient utilization of beekeeping and pollination, there is a need to explore its biology and management practices. In light of this, the current study was carried out to investigate the ontogeny and dietary differences in the queen and worker castes of the A. c. cerana honey bee. This article presents, supplemented by reference images, a detailed description of the life history of A. c. cerana queens and workers. Additionally, this study investigated the nutritional differences between royal jelly (RJ) and worker jelly (WJ) at various larval ages. The contents of the moisture, crude protein, and amino acids in RJ and WJ were determined via freeze drying, Kjeldahl nitrogen determination, and ultra-high performance liquid chromatography. The results highlight significant variations in the moisture content, crude protein concentration, and amino acid concentration between RJ and WJ. The results offer theoretical support for ex situ artificial rearing practices of A. c. cerana. Full article

Honeybees are some of the smallest farmed animals, and apiculture by-products, e.g., honey, beeswax, propolis, royal jelly, and pollen contribute to animal nutrition. For the effective production of these by-products, the optimal development and nutrient supply of the honeybee is required. Beginning with the development of the mouth and anal pores on the second day of embryonic development, the digestive tract differentiates into the mouth and fore-, mid-, and hindgut during the pupal stage. The various glands within the oral cavity are particularly important, secreting enzymes and substances that are crucial for digestion and hive nutrition, e.g., invertase and royal jelly. Honeybees rely on a specialized caste system, with worker bees collecting nectar, pollen, water, and resin for the nutrition of the entire hive. Macronutrients, including proteins, carbohydrates, and lipids, obtained primarily from pollen and nectar, are essential for the growth and development of larvae and the overall health of the colony. Inadequate nutrient intake can lead to detrimental effects on larval development, prompting cannibalism within the hive. Apiculture by-products possess unique nutritional and therapeutic properties, leading to a growing interest in the use of honey, beeswax, propolis, and pollen as a feed additive. In recent years, the use of apicultural by-products in animal nutrition has been primarily limited to in vivo studies, which have demonstrated various positive impacts on the performance of farm animals. Honey, beeswax, propolis, royal jelly, and pollen are listed feed stuffs according to Regulation (EC) No. 68/2013. However, for animal nutrition there is not any specific legal definition for these products and no legal requirements regarding their ingredients as given for honey or beeswax in European food law. Full article

Royal jelly is a secretion produced from the hypopharyngeal glands of worker bees, which requires significant pollen reserves to stimulate gland secretion. The natural sources of food available to the hive during beekeeping season can greatly affect the quantity and quality of produced royal jelly. In this study, samples of royal jelly were collected throughout the beekeeping season, and their physical and chemical characteristics were analyzed to understand how natural variations in bee diet affect royal jelly production. Before each sample collection, the bees’ food reserves were removed from the experimental colonies so that the royal jelly was produced solely from natural sources. The results showed that the production was significantly lower during the summer months compared with spring and autumn. Additionally, the moisture, protein, fructose, and glucose content of fresh royal jelly also showed significant changes in the summer, and all physical and chemical characteristics decreased when the fresh samples were converted into dry matter. It seems that the quality of pollen entering the hives has a direct impact on the physical and chemical properties of the final product, highlighting the crucial role of available resources in stimulating bees to produce royal jelly. Full article

The mandibular gland in worker bees synthesizes and secretes the organic acids present in royal jelly, and its development directly affects yield and quality. Therefore, we aimed to analyze the differences in morphology and gene expression in the mandibular glands of Apis mellifera carnica worker bees of different ages (3, 6, 9, 12, and 16 d). We dissected their mandibular glands and performed morphological and transcriptomic analyses to investigate the development of the mandibular gland and the molecular regulatory mechanisms involved in royal jelly secretion. Microscopy revealed that mandibular gland development is likely completed in the early stages. There were no significant differences in the structural morphology or organelles involved in the secretion of royal jelly at different ages. Transcriptomics revealed a total of 1554 differentially expressed genes, which were mainly involved in fat metabolism, lipid transport, and energy metabolism. The extracellular matrix–receptor interaction pathway was significantly enriched and contributed to the royal jelly secretion process. These results elucidate the genetic basis of the role of the mandibular gland in royal jelly secretion in A. mellifera and provide a reference for the genetic improvement of bees with high royal jelly production in the future. Full article

The glands of bees are responsible for generating and secreting various biologically active substances that significantly impact bee physiological health and adaptability. This study aimed to investigate the effects of adding citric acid (CA) to bee feed on gland development and royal jelly quality. By formulating feed with varying proportions of CA, evaluation was undertaken of pollen feeding by honeybees under laboratory conditions, along with the impact of CA on the development of major glands, to determine suitable addition proportions. Further optimization of the CA proportion involved feeding colonies and evaluating royal jelly production and quality. The results indicated that feed containing 0.75% CA significantly extended the lifespan of bees and increased their pollen consumption. Gland development in bees showed a positive correlation with CA addition within the range of 0.25% to 0.75%, especially at 0.50% and 0.75%, which notably accelerated the development of mandibular, hypopharyngeal, and cephalic salivary glands, with active proliferation and differentiation of glandular cells and maintenance of normal gland size and morphology. CA added to feed stimulated vigorous secretion of wax glands in worker bees, resulting in prolific wax construction. Colonies consuming feed containing 0.50% CA produced royal jelly with significantly reduced moisture and total sugar content and increased levels of 10-HDA, total phenolic acids, total proteins, and acidity. These findings demonstrate that CA consumption significantly prolongs bee lifespan, increases consumption, promotes gland development, and enhances royal jelly quality. This research provides theoretical guidance for beekeeping practices and feed development, contributing to the sustainable advancement of apiculture. Full article

Young workers, i.e., nurse honey bees, synthesize and secrete royal jelly to feed the brood and queen. Since royal jelly is a protein-rich substance, the quality of royal jelly may be influenced by the consumption of feed with varying protein content. We tested whether honey bee (Apis mellifera) colonies compensates for the nutritional quality to produce royal jelly by feeding different pollen patties made of oak or rapeseed pollen. After harvesting royal jelly, we examined the chemical composition including proximate nutrients, amino acids, proteins, fatty acids, and minerals of royal jelly samples obtained from two treatments. The results revealed that pollen patties with different nutritional levels did not influence the nutritional composition except for the crude fat. The levels of 10-HDA, which serves as an indicator of the royal jelly quality, showed no significant difference between the oak and rapeseed treatments, with values of 1.9 and 2.1 g/100 g, respectively. However, we found some differences in the protein intensity, particularly the MRJP3 precursor, MRJP3-like, and glucose oxidase. This study suggests that honey bees may have mechanisms to compensate for nutritional standards to meet the brood’s and queen’s nutritional requirements during bee pollen collection, preserving bee bread and royal jelly secretion. Full article

This study aimed to assess the impact of oleic acid (OA) supplementation on the biosynthesis of 10-hydroxy-2-decenoic acid (10-HDA) in Apis mellifera ligustica. In experiment 1, varying concentrations of OA (2%, 4%, 6% and 8%) were added to an artificial diet for newly emerged bees reared in cages. Analysis of 10-HDA content and gene expression in the mandibular gland (MG) revealed that the 8% OA treatment had the greatest impact on promoting the synthesis of 10-HDA. Subsequent investigations utilized RNA-seq and lipidomics to characterize the molecular signature in the MG after feeding the 8% OA diet. Phosphatidylcholine (PC) and triacylglycerol (TAG) were found to be the predominant lipids in the MG of worker bees. A total of 154 TAGs were identified, with TAG (18:1-18:1-18:1) exhibiting the highest abundance, which increased by 1.5 times. The major TAG species contained palmitic acid (16:0) and oleic acid (18:1) in their structure, which was associated with fatty acid composition of diet. The increase in abundance of main TAGs may be attributed to the upregulation of glycerol-3-phosphate acyltransferase (Gpat) and glycerol kinase (GK) gene expression at the transcriptional level. The upregulation of differentially expressed genes (DEGs) related to carbohydrate metabolism may contribute to meeting the heightened metabolic demands of the MGs in worker bees. Royal jelly (RJ) samples from bee colonies fed with the 8% OA diet exhibited higher 10-HDA level than RJ collected from bee colonies fed with the artificial diet. These results indicate that 8% OA addition in the diet enhanced biosynthesis of 10-HDA in the mandibular gland, which was accompanied by significant and highly species-selective remodeling of TAGs. Full article

A metagenomic analysis of the virome of honey bees (Apis mellifera) from an apiary with high rates of unexplained colony losses identified a novel RNA virus. The virus, which was named Apis mellifera solinvivirus 1 (AmSV1), contains a 10.6 kb positive-strand genomic RNA with a single ORF coding for a polyprotein with the protease, helicase, and RNA-dependent RNA polymerase domains, as well as a single jelly-roll structural protein domain, showing highest similarity with viruses in the family Solinviviridae. The injection of honey bee pupae with AmSV1 preparation showed an increase in virus titer and the accumulation of the negative-strand of AmSV1 RNA 3 days after injection, indicating the replication of AmSV1. In the infected worker bees, AmSV1 was present in heads, thoraxes, and abdomens, indicating that this virus causes systemic infection. An analysis of the geographic and historic distribution of AmSV1, using over 900 apiary samples collected across the United States, showed AmSV1 presence since at least 2010. In the year 2021, AmSV1 was detected in 10.45% of apiaries (95%CI: 8.41–12.79%), mostly sampled in June and July in Northwestern and Northeastern United States. The diagnostic methods and information on the AmSV1 distribution will be used to investigate the connection of AmSV1 to honey bee colony losses. Full article

Termites live in colonies, and their members belong to different castes that each have their specific role within the termite society. In well-established colonies of higher termites, the only food the founding female, the queen, receives is saliva from workers; such queens can live for many years and produce up to 10,000 eggs per day. In higher termites, worker saliva must thus constitute a complete diet and therein resembles royal jelly produced by the hypopharyngeal glands of honeybee workers that serves as food for their queens; indeed, it might as well be called termite royal jelly. However, whereas the composition of honeybee royal jelly is well established, that of worker termite saliva in higher termites remains largely unknown. In lower termites, cellulose-digesting enzymes constitute the major proteins in worker saliva, but these enzymes are absent in higher termites. Others identified a partial protein sequence of the major saliva protein of a higher termite and identified it as a homolog of a cockroach allergen. Publicly available genome and transcriptome sequences from termites make it possible to study this protein in more detail. The gene coding the termite ortholog was duplicated, and the new paralog was preferentially expressed in the salivary gland. The amino acid sequence of the original allergen lacks the essential amino acids methionine, cysteine and tryptophan, but the salivary paralog incorporated these amino acids, thus allowing it to become more nutritionally balanced. The gene is found in both lower and higher termites, but it is in the latter that the salivary paralog gene got reamplified, facilitating an even higher expression of the allergen. This protein is not expressed in soldiers, and, like the major royal jelly proteins in honeybees, it is expressed in young but not old workers. Full article

Honey bee colonies are resource rich and densely populated, generating a constant battle to control microbial growth. Honey is relatively sterile in comparison with beebread: a food storage medium comprising pollen mixed with honey and worker head-gland secretions. Within colonies, the microbes that dominate aerobic niches are abundant throughout social resource space including stored pollen, honey, royal jelly, and the anterior gut segments and mouthparts of both queens and workers. Here, we identify and discuss the microbial load in stored pollen associated with non-Nosema fungi (primarily yeast) and bacteria. We also measured abiotic changes associated with pollen storage and used culturing and qPCR of both fungi and bacteria to investigate changes in stored pollen microbiology by both storage time and season. Over the first week of pollen storage, pH and water availability decreased significantly. Following an initial drop in microbial abundance at day one, both yeasts and bacteria multiply rapidly during day two. Both types of microbes then decline at 3–7 days, but the highly osmotolerant yeasts persist longer than the bacteria. Based on measures of absolute abundance, bacteria and yeast are controlled by similar factors during pollen storage. This work contributes to our understanding of host–microbial interactions in the honey bee gut and colony and the effect of pollen storage on microbial growth, nutrition, and bee health. Full article