Identification of a novel hypocholesterolemic protein, major royal jelly protein 1, derived from royal jelly

Exploring the Therapeutic Potential of Royal Jelly in Metabolic Disorders and Gastrointestinal Diseases

Metabolic disorders, encompassing diabetes mellitus, cardiovascular diseases, gastrointestinal disorders, etc., pose a substantial global health threat, with rising morbidity and mortality rates. Addressing these disorders is crucial, as conventional drugs often come with high costs and adverse effects. This review explores the potential of royal jelly (RJ), a natural bee product rich in bioactive components, as an alternative strategy for managing metabolic diseases. RJ exhibits diverse therapeutic properties, including antimicrobial, estrogen-like, anti-inflammatory, hypotensive, anticancer, and antioxidant effects. This review's focus is on investigating how RJ and its components impact conditions like diabetes mellitus, cardiovascular disease, and gastrointestinal illnesses. Evidence suggests that RJ serves as a complementary treatment for various health issues, notably demonstrating cholesterol- and glucose-lowering effects in diabetic rats. Specific RJ-derived metabolites, such as 10-hydroxy-2-decenoic acid (10-HDA), also known as the "Queen bee acid," show promise in reducing insulin resistance and hyperglycemia. Recent research highlights RJ's role in modulating immune responses, enhancing anti-inflammatory cytokines, and suppressing key inflammatory mediators. Despite these promising findings, further research is needed to comprehensively understand the mechanisms underlying RJ's therapeutic effects.

Jelleine, a Family of Peptides Isolated from the Royal Jelly of the Honey Bees (Apis mellifera), as a Promising Prototype for New Medicines: A Narrative Review

The jelleine family is a group of four peptides (jelleines I-IV) originally isolated from the royal jelly of honey bee (Apis mellifera), but later detected in some honey samples. These oligopeptides are composed of 8-9 amino acid residues, positively charged (+2 to +3 at pH 7.2), including 38-50% of hydrophobic residues and a carboxamide C-terminus. Jelleines, generated by processing of the C-terminal region of major royal jelly proteins 1 (MRJP-1), play an important biological role in royal jelly conservation as well as in protecting bee larvae from potential pathogens. Therefore, these molecules present numerous benefits for human health, including therapeutic purposes as shown in preclinical studies. In this review, we aimed to evaluate the biological effects of jelleines in addition to characterising their toxicities and stabilities. Jelleines I-III have promising antimicrobial activity and low toxicity (LD50 > 1000 mg/Kg). However, jelleine-IV has not shown relevant biological potential. Jelleine-I, but not the other analogues, also has antiparasitic, healing, and pro-coagulant activities in addition to indirectly modulating tumor cell growth and controlling the inflammatory process. Although it is sensitive to hydrolysis by proteases, the addition of halogens increases the chemical stability of these molecules. Thus, these results suggest that jelleines, especially jelleine-I, are a potential target for the development of new, effective and safe therapeutic molecules for clinical use.

Royal jelly: a predictive, preventive and personalised strategy for novel treatment options in non-communicable diseases

Royal jelly (RJ) is a bee product produced by young adult worker bees, composed of water, proteins, carbohydrates and lipids, rich in bioactive components with therapeutic properties, such as free fatty acids, mainly 10-hydroxy-trans-2-decenoic acid (10-H2DA) and 10-hydroxydecanoic acid (10-HDA), and major royal jelly proteins (MRJPs), as well as flavonoids, most flavones and flavonols, hormones, vitamins and minerals. In vitro, non-clinical and clinical studies have confirmed its vital role as an antioxidant and anti-inflammatory. This narrative review discusses the possible effects of royal jelly on preventing common complications of non-communicable diseases (NCDs), such as inflammation, oxidative stress and intestinal dysbiosis, from the viewpoint of predictive, preventive and personalised medicine (PPPM/3PM). It is concluded that RJ, predictively, can be used as a non-pharmacological therapy to prevent and mitigate complications related to NCDs, and the treatment must be personalised.

The effects of royal jelly supplementation on anthropometric indices: a GRADE-assessed systematic review and dose-response meta-analysis of randomized controlled trials

Inconsistent data are available about the effect of royal jelly supplementation on anthropometric indices in humans. This systematic review and meta-analysis was done to summarize data from available randomized controlled trials (RCTs) on the effect of royal jelly supplementation on anthropometric indices such as body weight (BW), body mass index (BMI), and fat mass (FM) in adults. We systematically searched Embase, PubMed, Web of Science, and Scopus databases up to March 2023. All RCTs assessing the effect of royal jelly on anthropometric indices were included. Data were pooled using the random-effects method and were expressed as weighted mean difference (WMD) and 95% confidence intervals (CIs). Sensitivity and subgroup analyses were also performed. Out of 1,492 records, 10 studies that enrolled 512 participants were included. There was no significant effect on BW (WMD: -0.29 kg, 95% CI: -1.24, 0.65, p = 0.543), BMI (WMD: 0.11 kg/m2, 95% CI: -0.29, 0.52, p = 0.583), and FM (WMD: 0.02%, 95% CI: -0.41, 0.46, p = 0.84). However, we observed a reduction in BW and BMI following royal jelly intake in subgroup of royal jelly dosage <3,000 mg/day. Although the royal jelly supplementation significantly reduced BW and BMI at the dosages <3,000 mg/day, until additional trials have been conducted to assess the effects on obesity measures, it is best to prescribe royal jelly with caution.

Royal jelly mediates fibrotic signaling, collagen cross-linking and cell proliferation in cardiac fibroblasts

Royal jelly (RJ) is a multifunctional bee product with a unique composition and wide-ranging biological properties, including antioxidant, anti-inflammatory and antiproliferative activities. Still, little is known about the possible myocardial protective properties of RJ. Considering that sonication could enhance RJ bioactivity, this study aimed to assess the effects of non-sonicated (NS) and sonicated (S) RJ on fibrotic signaling, cell proliferation, and collagen production in cardiac fibroblasts. S-RJ was produced by ultrasonication at 20 kHz. Ventricular fibroblasts isolated from neonatal rats were cultured and treated with different concentrations of NS-RJ or S-RJ (0, 50, 100, 150, 200, and 250 µg/well). S-RJ significantly depressed the expression levels of transglutaminase 2 (TG2) mRNA across all the concentrations tested and was inversely associated with the expression of this profibrotic marker. S-RJ and NS-RJ displayed distinct dose-dependent effects on mRNA expression of several other profibrotic, proliferation, and apoptotic markers. Unlike NS-RJ, S-RJ elicited strong negative dose-dependent relationships with the expression of profibrotic markers (TG2, COL1A1, COL3A1, FN1, CTGF, MMP-2, α-SMA, TGF-β1, CX43, periostin), as well as proliferation (CCND1) and apoptotic (BAX, BAX/BCL-2) markers, indicating that RJ dose-response effects were significantly modified by sonification. NS-RJ and S-RJ increased the content of soluble collagen, while decreasing collagen cross-linking. Collectively, these findings show that S-RJ has a greater range of action than NS-RJ for downregulating the expression of biomarkers associated with cardiac fibrosis. Reduced biomarker expression and collagen cross-linkages upon cardiac fibroblast treatment with specific concentrations of S-RJ or NS-RJ suggests putative roles and mechanisms by which RJ may confer some protection against cardiac fibrosis.

Changes in the Histological Structure of Adrenal Glands and Corticosterone Level after Whey Protein or Bee Pollen Supplementation in Running and Non-Running Rats

Due to the many health-promoting properties of bee pollen and whey protein, both products are widely used as dietary supplements. According to these reports on their health-promoting properties, the aim of our study is to assess whether these products can influence the structure and function of the adrenal glands in rats. Thirty male Wistar rats were divided into six equal groups. Among them, there were three groups which included non-running rats and three groups which included running rats. Both of these running (n = 3) and non-running (n = 3) groups included non-supplemented (control groups), bee-pollen-supplemented groups, and whey-protein-supplemented groups. After 8 weeks, the rats were decapitated, their adrenal glands were collected, and paraffin slides were prepared. Then, staining according to the standard H&E and Masson's trichrome protocols was performed. Fecal and urine samples were collected prior to the end of the study to measure corticosterone levels. In the group of non-running rats, the consumption of bee pollen was noted to be significantly higher when compared to the group of running rats (p < 0.05). The thickness of the particular adrenal cortex layers was similar among all of the groups (p > 0.05). The statistically significant changes in the microscopic structure of the adrenal glands, especially regarding cell nuclei diameter and structure, as well as the architecture of sinusoids, were observed between the groups. Moreover, urine corticosterone concentrations were found to vary between all of the analyzed groups (p < 0.05). These results indicate that both bee pollen and whey protein have limited stress-reducing potential.

Bee Products as Interesting Natural Agents for the Prevention and Treatment of Common Cardiovascular Diseases

Apitherapy is a form of alternative therapy that relies on the use of bee products, i.e., honey, royal jelly, propolis, pollen, and bee venom (known as apitoxin), for the prevention and treatment of various diseases. Various in vitro and in vivo studies suggest that these products may be effective in the prophylaxis and treatment of cardiovascular diseases (CVDs). This mini-review of papers identified in various electronic databases describes new aspects of the bioactivity of certain bee products, viz. bee pollen, royal jelly, bee venom, propolis, and bee bread, as natural interesting products for the prevention and treatment of common CVDs.

Royal jelly fatty acids downregulate ANGPTL8 expression through the decrease in HNF4α protein in human hepatoma HepG2 cells

Royal jelly (RJ) intake has been reported to be effective for reducing serum lipids; however, the mechanism is not fully understood. Angiopoietin-like protein 8 (ANGPTL8), a secreted protein, plays a key role in lipid metabolism. In this study, we investigated the effects of specific fatty acids included in RJ (RJ fatty acids), such as 10-hydroxy-2-decenoic acid, 10-hydroxydecanoic acid, and sebacic acid (SA), on expression of ANGPTL8 in human hepatoma HepG2 cells. SA markedly reduced the expression of ANGPTL8. Reporter assay revealed that SA suppressed ANGPTL8 promoter activity. In addition, we identified a functional binding site of hepatocyte nuclear factor-4α (HNF4α), a liver-enriched transcription factor, in the ANGPTL8 promoter. SA reduced the levels of HNF4α protein and the binding of HNF4α to the ANGPTL8 promoter. Moreover, siRNA knockdown of HNF4α suppressed the expression of ANGTPL8 mRNA. Taken together, we conclude that SA downregulates ANGPTL8 expression via the decrease in HNF4α protein.

Possible Ameliorative Effects of the Royal Jelly on Hepatotoxicity and Oxidative Stress Induced by Molybdenum Nanoparticles and/or Cadmium Chloride in Male Rats

Simple Summary

The aim of the present investigation is valuable due to the importance of possible contaminations and negative effects of these cadmium chloride and molybdenum nanoparticles. The physicochemical properties of molybdenum nanoparticles have been characterized, as well as their ultrastructural organization. A rat experimental model was then employed to assess the liver toxicity of molybdenum nanoparticles, even in combination with CdCl₂. The toxicity of molybdenum nanoparticles and cadmium chloride was estimated via liver damage by means of chemico-biological markers of liver injury, serum lipids, inflammation, oxidative status, and histological and immunohistochemistry patterns. Moreover, the possible effects of royal jelly were evaluated. The results clarified that both chemicals induced hepatic toxicity with the excessive triggering of reactive oxygen species that induced severe oxidative injury, histological alterations in the hepatic structure, and hepatic ultrastructure. These results are concurrent with obtaining normal biochemical levels in groups either treated with royal jelly or even a combination of royal jelly and two xenobiotics. The royal jelly is considered an essential potential source of natural antioxidants capable of frustrating the effects of oxidative injury, which is considered the main cause of many diseases.

Abstract

The present study aimed to investigate the effect of the royal jelly (RJ) on hepatotoxicity induced by molybdenum nanoparticles (MoO₃-NPs), cadmium chloride (CdCl₂), or their combination in male rats at biochemical, inflammation, immune response, histological, and ultrastructural levels. The physicochemical properties of MoO₃-NPs have been characterized, as well as their ultrastructural organization. A rat experimental model was employed to assess the liver toxicity of MoO₃-NPs, even in combination with CdCl₂. Different cellular studies indicate divergent mechanisms, from increased reactive oxygen species production to antioxidative damage and cytoprotective activity. Seventy male rats were allocated to groups: (i) control; (ii) MoO₃-NPs (500 mg/kg); (iii) CdCl₂ (6.5 mg/kg); (iv) RJ (85 mg/kg diluted in saline); (v) MoO₃-NPs followed by RJ (30 min after the MoO₃-NPs dose); (vi) CdCl₂ followed by RJ; and (vii) a combination of MoO₃-NPs and CdCl₂, followed by RJ, for a total of 30 successive days. Hepatic functions, lipid profile, inflammation marker (CRP), antioxidant biomarkers (SOD, CAT, GPx, and MDA), and genotoxicity were examined. Histological changes, an immunological marker for caspase-3, and transmission electron microscope variations in the liver were also investigated to indicate liver status. The results showed that RJ alleviated the hepatotoxicity of MoO₃-NPs and/or CdCl₂ by improving all hepatic vitality markers. In conclusion, the RJ was more potent and effective as an antioxidant over the oxidative damage induced by the combination of MoO₃-NPs and CdCl₂.

Effect of royal jelly to deal with stress oxidative in preconception women: A literature review

INTRODUCTION

Oxidative stress that occurs in preconception women can disrupt the reproductive system to cause infertility. The antioxidants contained in royal jelly can overcome oxidative stress due to low antioxidants in the body. The purpose of this study is to examine studies of the content of royal jelly, antioxidant activity, and the effectiveness of royal jelly in dealing with oxidative stress in preconception women.

METHOD

This research method is an electronic database search using keywords according to questions in research from the online library PubMed, content science, and Science Direct.

RESULT

a study review conducted in 6 research journals stated that the use of royal jelly as a supplement containing 10-hydroxy-2-decanoic (10-HDA) increases glutathione levels, as well as lipid peroxidation inhibitors.

CONCLUSION

The effectiveness of royal jelly to overcome oxidative stress in preconception women can be assessed from the content of royal jelly and antioxidant activity that can increase the glutathione levels and inhibit increased lipid peroxidation, which is a sign of oxidative stress.

Dose-Dependent Effects of Royal Jelly on Estrogen- and Progesterone-Induced Mammary Gland Hyperplasia in Rats

SCOPE

Royal jelly (RJ) has a wide range of biological functions, its effect on hyperplasia of the mammary gland (HMG) in mammals is unclear. This study aims to investigate the effect of RJ on HMG and the dose-response relationship of RJ in the treatment of HMG.

METHODS AND RESULTS

HMG rats are induced by intramuscular injection of estrogen (E2) and progesterone, and are treated with different doses of RJ (100, 200, 400, and 800 mg kg^-1 d^-1 ). As a result, RJ improves the expansion of acinar and breast tissue ducts, particularly at 100 and 800 mg kg^-1 d^-1 . These two doses also inhibit serum E2 and prolactin (PRL) secretion and increase serum progesterone secretion and the expression of estrogen receptor (ER)-β in the breast tissue. In addition, 800 mg kg^-1 d^-1 decrease and increase the mRNA expression of, respectively, hypothalamic gonadotropin-releasing hormone (GnRH) and pituitary GnRH receptors (GnRH-R). The lowest dosage (100 mg kg^-1 d^-1 ) increases GnRH-R mRNA expression as well. However, the effects of 200 and 400 mg kg^-1 d^-1 RJ on the reproductive parameters of HMG are not significant, implying a dose-dependent effect.

CONCLUSION

RJ regulates endocrine dyscrasia in HMG rats and improves the breast tissue structure, indicating its potential in the prevention and treatment on HMG.

Royal Jelly Proteins and Their Derived Peptides: Preparation, Properties, and Biological Activities

Royal jelly, also called bee milk, is a source of high-quality proteins. Royal jelly proteins serve as not only a rich source of essential amino acids and functional donors but also an excellent substrate for preparing bioactive peptides. Most naturally occurring bioactive peptides in royal jelly are antibacterial, while peptides derived from proteolytic reactions are shown to exert antihypertensive, antioxidative, and anti-aging activities. Further studies are warranted to characterize the functional properties of major royal jelly proteins and peptides, to explore the preparation of bioactive peptides and the potential novel activities, to improve their bioavailability, to enhance the production efficiency for commercial availability, and finally to open up new applications for royal jelly as a functional food and potential therapeutic agent.

The Role of Bioactive Peptides in Diabetes and Obesity

Bioactive peptides are present in most soy products and eggs and have essential protective functions. Infection is a core feature of innate immunity that affects blood pressure and the glucose level, and ageing can be delayed by killing senescent cells. Food also encrypts bioactive peptides and protein sequences produced through proteolysis or food processing. Unique food protein fragments can improve human health and avoid metabolic diseases, inflammation, hypertension, obesity, and diabetes mellitus. This review focuses on drug targets and fundamental mechanisms of bioactive peptides on metabolic syndromes, namely obesity and type 2 diabetes, to provide new ideas and knowledge on the ability of bioactive peptide to control metabolic syndromes.

Bee Products: A Representation of Biodiversity, Sustainability, and Health

Biodiversity strengthens the productivity of any ecosystem (agricultural land, forest, lake, etc.). The loss of biodiversity contributes to food and energy insecurity; increases vulnerability to natural disasters, such as floods or tropical storms; and decreases the quality of both life and health. Wild and managed bees play a key role in maintaining the biodiversity and in the recovery and restoration of degraded habitats. The novelty character of this perspective is to give an updated representation of bee products’ biodiversity, sustainability, and health relationship. The role of bees as bioindicators, their importance in the conservation of biodiversity, their ecosystem services, and the variety of the bee products are described herein. An overview of the main components of bee products, their biological potentials, and health is highlighted and detailed as follows: (i) nutritional value of bee products, (ii) bioactive profile of bee products and the related beneficial properties; (iii) focus on honey and health through a literature quantitative analysis, and (iv) bee products explored through databases. Moreover, as an example of the interconnection between health, biodiversity, and sustainability, a case study, namely the “Cellulose Park”, realized in Rome (Italy), is presented here. This case study highlights how bee activities can be used to assess and track changes in the quality of agricultural ecosystems—hive products could be valid indicators of the quality and health of the surrounding environment, as well as the changes induced by the biotic and abiotic factors that impact the sustainability of agricultural production and biodiversity conservation in peri-urban areas.

Combined effects of royal jelly and environmental enrichment against stress-induced cognitive and behavioral alterations in male rats: behavioral and molecular studies

BACKGROUND

Exposure to chronic stress has detrimental effects on cognitive and emotional processing. Also, the neuroprotective influences of environmental enrichment (EE) and royal jelly (RJ) have been indicated in previous studies.

AIMS

To our knowledge, to date, there are no studies about the synergistic effects of EE and RJ on cognitive changes induced by stress. Therefore, this study aimed to investigate the protective effects of RJ, and EE on anxiety-like behaviors, cognitive functions, and expression of hippocampal and also prefrontal cortex (PFC) brain-derived neurotrophic factor (BDNF) levels in stressed rats.

METHODS

By using restraint and cold temperature, rats were exposed to stressful situations and then subjected to treatment with RJ or/ and EE for 14 days. Stress induction was done 14 days before treatments by placing the rats in the restrainer under 4°C. Following the interventions, anxiety-like behaviors, novel object recognition memory (NORM), inhibitive avoidance performance, hippocampal, and PFC BDNF expression were examined. The plasma corticosterone level of all groups was also evaluated.

RESULTS

Results showed increased plasma corticosterone levels, stress-induced deficits in the NORM and IA tests, and increased anxiety-like behaviors. EE and RJ improved these deficits with a decline in serum corticosterone and also increased BDNF levels in the hippocampus and PFC in stressed ones.

CONCLUSION

The EE and the RJ prevented the detrimental effects of stress on anxiety-like behaviors and memory processes. These treatments can protect susceptible brain areas against chronic stress via improvement in behavioral and cognitive impairments through mediating BDNF expression.

Multifunctionality and intrinsic disorder of royal jelly proteome

Royal Jelly (RJ) is a gelatinous white-yellowish fluid, possessing a sour taste and a slight phenolic smell that is secreted by the hypopharyngeal and mandibular salivary glands of the nurse honeybees, and is used in nutrition of larvae and adult queens. Similar to other substances associated with the activities of honeybees, RJ not only contains nutritive components, such as carbohydrates, proteins, peptides, lipids, vitamins, and mineral salts, but also represents a natural ingredient with cosmetic and health-promoting properties. RJ is characterized by remarkable multifunctionality, possessing numerous biological activities. Although this multifunctionality of RJ can be considered as a consequence of its complex nature, many proteins and peptides in RJ are polyfunctional entities themselves. In this article, we show that RJ proteins contain different levels of intrinsic disorder, have sites of post-translational modifications, can be found in multiple isoforms, and many of them possess disorder-based binding sites, suggesting that the conformational ensembles of the RJ proteins might undergo change as a result of their interaction with specific binding partners. All these observations suggest that the multifunctionality of proteins and peptides from RJ is determined by their structural heterogeneity and polymorphism, and serve as an illustration of the protein structure-function continuum concept.

Health Promoting Properties of Bee Royal Jelly: Food of the Queens

Royal jelly (RJ) demand is growing every year and so is the market for functional foods in general. RJ is formed by different substances, mainly carbohydrates, proteins, and lipids, but also vitamins, minerals, and phenolic or volatile compounds in lower proportion. Major royal jelly proteins (MRJP) are, together with 10-hydroxy-2-decenoic acid (10-HDA), key substances of RJ due to their different biological properties. In particular, 10-HDA is a unique substance in this product. RJ has been historically employed as health enhancer and is still very relevant in China due to the traditional medicine and the apitherapy. Nowadays, it is mainly consumed as a functional food or is found in supplements and other formulations for its health-beneficial properties. Within these properites, anti-lipidemic, antioxidant, antiproliferative, antimicrobial, neuroprotective, anti-inflammatory, immunomodulatory, antiaging, and estrogenic activities have been reported for RJ or its specific components. This manuscript is aimed at reviewing the current knowledge on RJ components, their assessment in terms of authenticity, their biological activities, and related health applications.

Improved bioavailability of EGCG after complexation with royal jelly protein

This study was designed to check whether complexation of royal jelly (RJ) proteins with green tea extract enriched with EGCG, would enhance the bioavailability on C2BBe1 cells. The total phenolic and EGCG of green tea extract (GTex) as well as the protein level of RJ were measured. The best entrapment efficiency (30.47%) was noted at a 10:4 ratio (RJ:EGCG of GTex) to confirm the maximum EGCG-RJ complexation. Followed by in vitro studies to check the cytotoxicity, morphological changes, EGCG uptake, and TBARS (antioxidant) activity were evaluated on C2BBe1 cells. The EGCG-RJ protein complex showed less toxicity without any morphological changes with better cellular EGCG uptake than GTex or GTex-RJ mixture on CeBBe1 cells. Besides, the EGCG-RJ protein complex display maximum TBARS suppressing activity to showcase better stability. This study infers that complexation of RJ proteins with EGCG (EGCG-RJ protein complex) could significantly improve the bioavailability of EGCG. PRACTICAL APPLICATIONS: EGCG is the major active component of green tea, which is responsible for various biological functions. Previous studies have indicated that complexation of EGCG with proteins (act as a carrier) could considerably improve the bioavailability of EGCG. Hence, the author speculates that complexation or combination of RJ with green tea (EGCG), might improve the bioavailability as well as enhance its biological properties. The outcome of this cell line study showed that the EGCG-RJ protein complex showed better bioavailability than EGCG or GTex, and thus, indicating that this novel complex can be used in the future for better EGCG bioavailability with improved biological function. However, further studies are needed to confirm the types of interaction and the reason for better bioavailability.

Royal Jelly-A Traditional and Natural Remedy for Postmenopausal Symptoms and Aging-Related Pathologies

Women's life stages are based on their reproductive cycle. This cycle begins with menstruation and ends with menopause. Aging is a natural phenomenon that affects all humans, and it is associated with a decrease in the overall function of the organism. In women, aging is related with and starts with menopause. Also, during menopause and postmenopausal period, the risk of various age-related diseases and complaints is higher. For this reason, researchers were pushed to find effective remedies that could promote healthy aging and extended lifespan. Apitherapy is a type of alternative medicine that uses natural products from honeybees, such as honey, propolis, royal jelly, etc. Royal jelly is a natural yellowish-white substance, secreted by both hypopharyngeal and mandibular glands of nurse bees, usually used to feed the queen bees and young worker larvae. Over the centuries, this natural product was considered a gold mine for traditional and natural medicine, due to its miraculous effects. Royal jelly has been used for a long time in commercial medical products. It has been demonstrated to possess a wide range of functional properties, such as: antibacterial, anti-inflammatory, vasodilatative, hypotensive, anticancer, estrogen-like, antihypercholesterolemic, and antioxidant activities. This product is usually used to supplement various diseases such as cardiovascular disease, Alzheimer's disease, sexual dysfunctions, diabetes or cancer. The main objective of this study is to highlight the effectiveness of royal jelly supplementation in relieving menopause symptoms and aging-related diseases. We also aimed to review the most recent research advances regarding the composition of royal jelly for a better understanding of the effects on human health promotion.

New Insights into the Biological and Pharmaceutical Properties of Royal Jelly

Royal jelly (RJ) is a yellowish-white and acidic secretion of hypopharyngeal and mandibular glands of nurse bees used to feed young worker larvae during the first three days and the entire life of queen bees. RJ is one of the most appreciated and valued natural product which has been mainly used in traditional medicines, health foods, and cosmetics for a long time in different parts of the world. It is also the most studied bee product, aimed at unravelling its bioactivities, such as antimicrobial, antioxidant, anti-aging, immunomodulatory, and general tonic action against laboratory animals, microbial organisms, farm animals, and clinical trials. It is commonly used to supplement various diseases, including cancer, diabetes, cardiovascular, and Alzheimer's disease. Here, we highlight the recent research advances on the main bioactive compounds of RJ, such as proteins, peptides, fatty acids, and phenolics, for a comprehensive understanding of the biochemistry, biological, and pharmaceutical responses to human health promotion and life benefits. This is potentially important to gain novel insight into the biological and pharmaceutical properties of RJ.

Identification of a novel cholesterol-lowering dipeptide, phenylalanine-proline (FP), and its down-regulation of intestinal ABCA1 in hypercholesterolemic rats and Caco-2 cells

There has been no report about in vivo active cholesterol-lowering dipeptide in any protein origin, despite their potential health benefits. Cattle heart protein hydrolysate ultra-filtrate (HPHU, molecular weight < ca. 1,000 Da peptide mixture) exhibits cholesterol-lowering activity in hypercholesterolemic rats, but the active peptide in HPHU that lowers serum cholesterol levels and its molecular mechanism are unknown. In this study, we separated and purified HPHU to identify a novel cholesterol-lowering dipeptide (phenylalanine-proline, FP) and characterized the mechanism underlying its effects in vivo and in vitro. We identified FP as an active peptide from HPHU by MALDI-TOF mass spectrometry. FP significantly decreased serum total and non-HDL cholesterol and hepatic cholesterol levels in rats. FP significantly increased serum HDL cholesterol, accompanied by a significant decrease in the atherogenic index. FP also significantly increased fecal cholesterol and acidic steroid excretion. Moreover, FP significantly decreased ATP-binding cassette transporter A1 (ABCA1) expression in the rat jejunum and reduced cholesterol absorption in Caco-2 cells. We found a novel cholesterol-lowering dipeptide FP that could improve cholesterol metabolism via the down-regulation of intestinal ABCA1. The cholesterol-lowering action induced by FP was disappeared in PepT1KO mice. FP-induced cholesterol-lowering action is mediated via PepT1 in mice.

Does in Ovo Injection of Two Chicken Strains with Royal Jelly Impact Hatchability, Post-Hatch Growth Performance and Haematological and Immunological Parameters in Hatched Chicks?

Simple Summary

The present investigation examined improvements in egg hatchability and the growth performance of hatched chicks of two strains upon injection with increasing concentrations of royal jelly (RJ). The results showed positive effects of RJ injection on all parameters. Limited impacts of the different chicken strains were observed on the tested parameters. The study revealed that varying the chicken strain could alter the response to the in ovo injection with RJ.

Abstract

The hypothesis of the present work was that the effects of in ovo injection may differ in different chicken strains. The influence of in ovo royal jelly (RJ) injection on hatching, growth and blood parameters in two chicken strains (Dokki-4 and El-Salam as example for different strains) was evaluated. A total of 1080 eggs were used. On the seventh day of incubation, the eggs were randomly allocated into six experimental groups in a 2 × 3 arrangement that included the two chicken strains and three concentrations of RJ (0, 0.25 and 0.5 mL RJ/egg). Injection with 0.5 mL RJ/egg improved hatchability compared to the other treatments. The El-Salam strain exhibited significantly higher body weight and body weight gain than the Dokki-4 strain. Injection with 0.5 mL RJ/egg significantly (p < 0.05) improved chicken body weight and daily weight gain compared to the control treatment. RJ injection decreased blood lipid profile parameters and the numbers of monocytes and eosinophils and increased total protein, globulin, haemoglobin (Hb) and lymphocyte levels compared to the control treatment. The Dokki-4 strain showed significantly higher antibody titres against avian influenza virus (AIV) (p < 0.05) and sheep red blood cells (SRBCs) (p < 0.0001) than the El-Salam strain and RJ injection enhanced antibody titres against AIV, Newcastle disease virus (NDV) and SRBCs. Therefore, the Dokki-4 strain was superior to the El-Salam strain for the tested parameters and injection with 0.5 mL RJ/egg produced the best hatching parameters, growth performance and health-related traits. RJ in ovo injection was much more effective in the Dokki-4 strain than in the El-Salam strain, which supported the hypothesis of the study that varying the chicken strain could alter the response to the in ovo injection with RJ.

Bioinformatics and Therapeutic Insights on Proteins in Royal Jelly

Background:

To date, there is no x-ray crystallography or structures from nuclear magnetic resonance (NMR) on royal jelly proteins available in the online data banks. In addition, characterization of proteins in royal jelly is not fully accomplished to date. Although new investigations unravel novel proteins in royal jelly, the majority of a protein family is present in high amounts (80-90%).

Objective:

In this review, we attempted to predict the three-dimensional structure of royal jelly proteins (especially the major royal jelly proteins) to allow visualization of the four protein surface properties (aromaticity, hydrophobicity, ionizability and (hydrogen (H)-bond) by using bioinformatics tools. Furthermore, we gathered the information on available therapeutic activities of crude royal jelly and its proteins.

Methods:

For protein modeling, prediction and analysis, the Phyre2 web portal systematically browsed in which the modeling mode was intensive. On the other side, to build visualized understanding of surface aromaticity, hydrophobicity, ionizability and H-bond of royal jelly proteins, the Discovery Studio 4.1 (Accelrys Software Inc.) was used.

Results:

Our in silico study confirmed that all proteins treasure these properties, including aromaticity, hydrophobicity, ionizability and (hydrogen (H)-bond. Another finding was that newly discovered proteins in royal jelly do not belong to the major royal jelly protein group.

Conclusion:

In conclusion, the three dimensional structure of royal jelly proteins along with its major characteristics were successfully elucidated in this review. Further studies are warranted to elucidate the detailed physiochemical properties and pharmacotherapeutics of royal jelly proteins.

Architecture of the native major royal jelly protein 1 oligomer

Honeybee caste development is nutritionally regulated by royal jelly (RJ). Major royal jelly protein 1 (MRJP1), the most abundant glycoprotein among soluble royal jelly proteins, plays pivotal roles in honeybee nutrition and larvae development, and exhibits broad pharmacological activities in humans. However, its structure has long remained unknown. Herein, we identify and report a 16-molecule architecture of native MRJP1 oligomer containing four MRJP1, four apisimin, and eight unanticipated 24-methylenecholesterol molecules at 2.65 Å resolution. MRJP1 has a unique six-bladed β-propeller fold with three disulfide bonds, and it interacts with apisimin mainly by hydrophobic interaction. Every four 24-methylenecholesterol molecules are packaged by two MRJP1 and two apisimin molecules. This assembly dimerizes to form an H-shaped MRJP1₄-apisimin₄-24-methylenecholesterol₈ complex via apisimin in a conserved and pH-dependent fashion. Our findings offer a structural basis for understanding the pharmacological effects of MRJPs and 24-methylenecholesterol, and provide insights into their unique physiological roles in bees.

Quantification of Major Royal Jelly Protein 1 in Fresh Royal Jelly by Ultraperformance Liquid Chromatography-Tandem Mass Spectrometry

Major royal jelly protein 1 (MRJP1) is the most abundant protein in royal jelly (RJ), and the level of MRJP1 has been suggested as a promising parameter for standardization and evaluation of RJ authenticity in quality. Here, a quantitative method was developed for the quantification of MRJP1 in RJ based on a signature peptide and a stable isotope-labeled internal standard peptide FFDYDFGSDER*(R*, ¹³C₆, ¹⁵N₄) by ultraperformance liquid chromatography-tandem mass spectrometry. Recoveries of the established method ranged from 85.33 to 95.80%, and both the intra- and interday precision were RSD < 4.97%. Quantification results showed that content of MRJP1 in fresh RJ was 41.96-55.01 mg/g. Abnormal levels of MRJP1 were found in three commercial RJs and implied that these samples were of low quality and might be adulterated. Results of the present work suggested that the developed method could be successfully applied to quantify MRJP1 in RJ and also could evaluate the quality of RJ.

Adaptogenic potential of royal jelly in liver of rats exposed to chronic stress

Restraint and cold stress increase both corticosterone and glycemia, which lead to oxidative damages in hepatic tissue. This study assessed the effect of royal jelly (RJ) supplementation on the corticosterone level, glycemia, plasma enzymes and hepatic antioxidant system in restraint and cold stressed rats. Wistar rats were allocated into no-stress, stress, no-stress supplemented with RJ and stress supplemented with RJ groups. Initially, RJ (200mg/Kg) was administered for fourteen days and stressed groups were submitted to chronic stress from the seventh day. The results showed that RJ supplementation decreases corticosterone levels and improves glycemia control after stress induction. RJ supplementation also decreased the body weight, AST, ALP and GGT. Moreover, RJ improved total antioxidant capacity, SOD activity and reduced GSH, GR and lipoperoxidation in the liver. Thus, RJ supplementation reestablished the corticosterone levels and the hepatic antioxidant system in stressed rats, indicating an adaptogenic and hepatoprotective potential of RJ.

Effects of chitosan scaffold along with royal jelly or bee venom in regeneration of critical sized radial bone defect in rat

The aim of this study was to compare the efficacy of honey bee venom (BV) and royal jelly (RJ) alongside chitosan scaffold (CS) in improving radius bone defect in rats. A total of 60 full thickness radial bone defects with a length of 5 mm were created in 60 male Wistar rats. Six healthy radial bones (3 rats) were also assigned as normal control for biomechanical studies. The defects were left empty (untreated group) or were filled by the autograft (autograft group), CS (CS group), CS alongside the BV solution (CS-BV group), and CS alongside the RJ solution (CS-RJ group). Healing of the bone defects were evaluated clinically and radiologically on days 0, 28, 42 and 56 after operation while the biomechanical testing and histopathological examination were performed on the 56th day after surgery. The autograft was more radiopaque than the untreated and CS groups at the 28th, 42nd and 56th postoperative days (P<0.05). The CS-BV and CS-RJ groups showed significantly higher radiographic outcomes than the untreated and CS groups at the 56th post-operative day (P<0.05). The density of osseous tissue (DOT) and the osteocytes and osteoblasts count of the CS-RJ and CS-BV groups were significantly higher than the CS and autograft groups (P<0.05). The biomechanical results of the CS-RJ group were significantly superior to the autograft, while the biomechanical properties of CS-BV group were not significantly different with the autograft group (P>0.05). The scaffolds in CS group were observable in the surgical site after 56 days. There was no significant difference in radiographs, DOT, cartilage tissue and fibrous tissue, and also biomechanical performances of the CS-BV and CS-RJ groups at the 42nd and 56th day after surgery. The untreated and CS groups showed weakest biomechanical results among all groups. It could be concluded that both treatment strategies in the CS-BV and CS-RJ groups were appropriate and useful in treating critical bone defects.

Hypocholesterolemic efficacy of royal jelly in healthy mild hypercholesterolemic adults

CONTEXT

Royal jelly (RJ) has been reported for its health promoting factors such as antioxidant, anti-inflammatory and lipid lowering activities.

OBJECTIVE

The present randomized, placebo-controlled study examines the hypolipidemic beneficial effect of RJ through evaluating anthropometric measurements, lipid profile and various hormone levels in mildly hypercholesterolemic participants.

MATERIALS AND METHODS

Forty subjects with mild hypercholesterolemia (180-200 mg/dL) were randomly selected and divided into two groups as experimental or placebo, who requested to intake nine capsules (350 mg/capsule) of RJ or placebo/day, respectively, for three months with one month of follow-up without any supplementation.

RESULTS

No significant changes were noted in any of the anthropometric parameters like body weight, waist and body fat. The serum total cholesterol (TC; 207.05-183.15 mg/dL) and low-density lipoprotein cholesterol (LDL-c; 126.44-120.31 mg/dL) levels were reduced significantly (p < 0.05) after administration of RJ. However, triglyceride (TG) and high-density lipoprotein cholesterol (HDL-c) levels were not considerably altered. Moreover, three months of RJ consumption significantly ameliorated (p < 0.05) the concentration of sex hormones like dehydroepiandrosterone sulphate (DHEA-S; 1788.09-1992.31 ng/mL). Also, intake of RJ did not elicit any hepatic or renal damage.

DISCUSSION AND CONCLUSION

Intervention with RJ for three months considerably lowered the TC and LDL-c levels through improving the levels of DHEA-S and thus alleviates the risk of cardiovascular disease (CVD).

The effect of royal jelly on the growth of breast cancer in mice

Due to various pharmacological properties, including antioxidative, anti-inflammatory and antibiotic properties, royal jelly (RJ) has been widely consumed in daily diets in numerous countries. In the present study, the effect of RJ on 4T1-bearing mice was investigated. The study was performed by feeding 4T1-bearing mice with RJ using either the prophylactic-therapeutic (PTRJ) or therapeutic (TRJ) method. The experimental results for the PTRJ group demonstrated that the weight of tumor was significantly reduced (RJ 0.5 and 1.5 g/kg); and in the serum, the levels of interleukin (IL)-2 (RJ 0.5 and 1.5 g/kg), interferon (IFN)-α, superoxide dismutase (SOD) and total antioxidant capacity (T-AOC) were significantly elevated, but the concentrations of IL-4 (RJ 0.5 and 1.5 g/kg) and IL-10 (RJ 1.0 g/kg) were significantly decreased. In addition, the activities of T-AOC and glutathione reductase (GR) were significantly improved in the liver, whereas in the kidney, the activities of T-AOC and GR were significantly increased only under the dose of 0.5 g/kg. For the TRJ group, the antitumor effect of RJ was not significant; the change in IL-2, IFN-α, SOD and T-AOC levels in the serum, and the change in T-AOC and GR in liver were similar to those observed in the PTRJ groups. RJ treatment was demonstrated to reduce the development of breast tumor in mice, and simultaneously improve the antioxidant capacity of the serum, liver and kidney, particularly using the prophylactic-therapeutic method. These results corroborated the efficacy of RJ supplementation in diets. The results of the present study suggest that the antioxidant and immunomodulatory activities of RJ serve an important role on antitumor growth.

Royal jelly decreases corticosterone levels and improves the brain antioxidant system in restraint and cold stressed rats

Restraint and cold stress induces the hypothalamic-pituitary-adrenal (HPA) axis to release corticosterone from the adrenal gland, which can worsen the antioxidant defense system in the central nervous system. Here, we investigated the corticosterone levels and the antioxidant defense system in the cerebellum and brain, as well as in its isolated regions, such as cerebral cortex, striatum and hippocampus of stressed rats supplemented with royal jelly (RJ). Wistar rats were supplemented with RJ for 14days and the stress induction started on the 7th day. Stressed rats increased corticosterone levels, glycemia and lipid peroxidation in the brain and cerebellum, cerebral cortex and hippocampus besides reduced glutathione defense system in the brain and striatum. Rats supplemented with RJ decreased corticosterone, maintained glycemia and decreased lipid peroxidation in the brain, cerebellum, as well as striatum and hippocampus, besides improved glutathione defense system in cerebral cortex and striatum. This study suggests an anti-stress and neuroprotective effect of RJ under stress conditions.

Therapeutic Properties of Bioactive Compounds from Different Honeybee Products

Honeybees produce honey, royal jelly, propolis, bee venom, bee pollen, and beeswax, which potentially benefit to humans due to the bioactives in them. Clinical standardization of these products is hindered by chemical variability depending on honeybee and botanical sources, but different molecules have been isolated and pharmacologically characterized. Major honey bioactives include phenolics, methylglyoxal, royal jelly proteins (MRJPs), and oligosaccharides. In royal jelly there are antimicrobial jelleins and royalisin peptides, MRJPs, and hydroxy-decenoic acid derivatives, notably 10-hydroxy-2-decenoic acid (10-HDA), with antimicrobial, anti-inflammatory, immunomodulatory, neuromodulatory, metabolic syndrome preventing, and anti-aging activities. Propolis contains caffeic acid phenethyl ester and artepillin C, specific of Brazilian propolis, with antiviral, immunomodulatory, anti-inflammatory and anticancer effects. Bee venom consists of toxic peptides like pain-inducing melittin, SK channel blocking apamin, and allergenic phospholipase A2. Bee pollen is vitaminic, contains antioxidant and anti-inflammatory plant phenolics, as well as antiatherosclerotic, antidiabetic, and hypoglycemic flavonoids, unsaturated fatty acids, and sterols. Beeswax is widely used in cosmetics and makeup. Given the importance of drug discovery from natural sources, this review is aimed at providing an exhaustive screening of the bioactive compounds detected in honeybee products and of their curative or adverse biological effects.

Identification of the active protein in rice bran protein having an inhibitory activity of cholesterol micellar solubility

In our previous study, rice bran protein (RBP) inhibited cholesterol micellar solubility in vitro and decreased serum cholesterol level in rats. In the present study, RBP was separated and purified by size-exclusion chromatography and reversed-phase chromatography. The active protein of RBP related to cholesterol micellar solubility was identified as lectin and non-specific lipid-transfer protein 1 using MALDI-TOF mass spectrometry analysis.

Greek-origin royal jelly improves the lipid profile of postmenopausal women

AIM

Menopause transition is associated with chronic conditions such as osteoporosis and cardiovascular disease. Concerns about the long-term safety of menopausal hormone therapy make alternative natural methods an appealing approach to management. The aim of this study was to examine the effect of royal jelly (RJ) on cardiovascular and bone turnover markers in clinically healthy postmenopausal women.

METHODS

A total of 36 postmenopausal healthy women were studied in a prospective follow-up study. Participants received 150 mg of RJ daily for three months. Circulating cardiovascular risk markers [lipid profile, antithrombin-III (ATIII), Protein C, Protein S, Plasminogen Activator Inhibitor-1 (PAI-1)] and bone turnover parameters [Total calcium, phosphate (P), parathormone (PTH), total type-1 Procollagen N-terminal (P1NP), Osteocalcin and serum collagen type 1 cross-linked C-telopeptide (CTX)] were compared between the baseline and the three-month visit.

RESULTS

The RJ used in this study was particularly rich in medium chain fatty acids, compounds with hypolipidemic properties, which comprised 63% of the dry weight fatty content. RJ treatment resulted in a significant increase in high density lipoprotein - cholesterol (HDL-C 60.2 mg/dL ± 12.3 versus 64.7 mg/dL ± 13.9, 7.7% increase, p = 0.0003), as well as in a significant decrease in low density lipoprotein - cholesterol (LDL-C, 143.9 ± 37.5 versus 136.2 ± 32, 4.1% decrease, p = 0.011) and in total cholesterol (224.4 ± 38.6 to 216.1 ± 36.5, 3.09% decrease, p = 0.018). No statistical significant changes were found in the remaining cardiovascular or the bone turnover parameters.

CONCLUSIONS

The intake of RJ 150 mg for three months is associated with significant improvements of the lipid profile of postmenopausal women. RJ supplementation may offer an alternative method of controlling the menopause - associated dyslipidemia.

Economic analysis of Royalactin production under uncertainty: Evaluating the effect of parameter optimization

Royalactin is a protein with several different potential uses in humans. Research, in insects and in mammalian cells, has shown that it can accelerate cell division and prevent apoptosis. The method of action is through the use of the epidermal growth factor receptor, which is present in humans. Potential use in humans could be to lower cholesterolemic levels in blood, and to elicit similar effects to those seen in bees, e.g., increased lifespan. Mass production of Royalactin has not been accomplished, though a recent article presented a Pichia pastoris fermentation and recovery by aqueous two-phase systems at laboratory scale as a possible basis for production. Economic modelling is a useful tool with which compare possible outcomes for the production of such a molecule and in particular, to locate areas where additional research is needed and optimization may be required. This study uses the BioSolve software to perform an economic analysis on the scale-up of the putative process for Royalactin. The key parameters affecting the cost of production were located via a sensitivity analysis and then evaluated by Monte Carlo analysis. Results show that if titer is not optimized the strategy to maintain a low cost of goods is process oriented. After optimization of this parameter the strategy changes to a product-oriented and the target output becomes the critical parameter determining the cost of goods. This study serves to provide a framework for the evaluation of strategies for future production of Royalactin, by analyzing the factors that influence its cost of manufacture.