Effects Of Royal Jelly Research Articles

Effects of royal jelly and its extracts on endometrial receptivity and MCF-7 cell growth in rats with thin endometrium

Royal jelly (RJ) is rich in various nutrients, including proteins and amino acids. RJ consumption improves sexual and urinary function in postmenopausal women, possibly owing to its hormone-like effects. Currently, hormone regulation and assisted reproductive technologies are widely used to treat thin endometria; however, high doses of these drugs can add to liver burden. In this study, RJ proteins and fatty acids were isolated, and their therapeutic effects on thin endometria were investigated in vivo and in vitro to verify their hormone-like regulatory effects. The results showed that RJ and its extracts could regulate endometrial receptivity-related factor expression levels in rats with a thin endometrium, accelerate MCF-7 cell apoptosis, and increase estrogen receptor expression in MCF-7 cells wherein. The estrogen-like effects of RJ and the fatty acids may be the main contributors. RJ may be a potential natural hormone replacement therapy.

Long-term administration of royal jelly regulates age-related disorders and improves gut function in naturally aging mice.

A natural aging mouse model can exhibit physiological characteristics that closely resemble those of human aging. Through long-term observation, it reflects the occurrence and development of the aging process more accurately. Although numerous beneficial effects of royal jelly (RJ) have been extensively demonstrated in multiple experimental models, the effects of RJ on naturally aging mice have not yet been investigated. In this study, middle-aged male C57BL/6J mice were given RJ for 9 consecutive months to investigate its impact on the intestinal barrier function, gut microbiota, short-chain fatty acids (SCFAs) content and possible mechanisms. The results confirmed that RJ modulated serum lipids by reducing the levels of total cholesterol (TC), triglycerides (TG), and low-density lipoprotein cholesterol (LDL-C). Additionally, it protected the liver by increasing antioxidant enzyme levels while decreasing inflammatory cytokines TNF-α (by 51.97%), IL-6 (by 29.73%), and IL-1β (by 43.89%). Furthermore, RJ inhibited the expression of cell cycle-dependent kinase inhibitors including p16, p21, and p53. Importantly, RJ ameliorated gut dysfunctions by inhibiting reduction of tight junction proteins and reducing inflammatory cytokines content in the colon. We also observed an alteration in gut microbiota characterized by an elevated ratio of Firmicutes to Bacteroides (F/B) along with increased abundance of beneficial bacteria, i.e., Lachnospiraceae NK4A136 and Akkermansia. Correlation analysis revealed positive associations between most bacterial genera and SCFAs production. Functional profiling of gut microbiota composition indicated that RJ intervention regulated amino acid metabolism, glycan biosynthesis, and cofactor/vitamin metabolism. Overall, our findings provide an effective dietary intervention strategy for modulating age-associated frailty through the modulation of the gut microbiota.

Effect of royal jelly on acrylamide-induced neurotoxicity in rats

Royal Jelly (RJ) is a natural product made by nurse bees known for its multiple therapeutic properties. The research aims to discover the ability of RJ to improve the hematological alterations and neurotoxicity caused by acrylamide (AA). The study rats were separated equally into four groups (6 in each group), the control group, the AA (38.27 mg/kg bw) group, the RJ (150 mg/kg bw) + AA group, and the RJ (300 mg/kg bw) + AA group. Blood and brain samples were collected after 10 days to evaluate haematological and biochemical parameters and to examine histopathological and immunohistochemistry. The administration of AA increased the level of malondialdehyde (MDA), decreases levels of haematological parameters, superoxide dismutase (SOD), reduced glutathione (GSH), brain-derived neurotrophic factor (BDNF), neurotransmitters (serotonin, dopamine, and acetylcholine), and cleaved caspase-3, as well as increase the damage to the brain tissues. Meanwhile, RJ improved levels of haematological parameters, oxidative stress parameters (MDA, SOD, and GSH), BDNF, neurotransmitters, cleaved caspase-3, and brain tissue damage induced by AA. The study demonstrated the protective impact of RJ against the haematological alterations and neurotoxicity caused by AA.

Effects of royal jelly on the antisenescence, mitochondrial viability and osteogenic differentiation capacity of umbilical cord-derived mesenchymal stem cells.

Mesenchymal stem cells (MSCs) are multipotent cells that have the ability to self-renew and regulate paracrine signalling and immune system processes. MSCs have extensive clinical applications in regeneration, functional reconstruction and cellular therapies. However, studies are needed to discover ways to improve the properties of MSCs, such as differentiation, and prevent senescence in culture, which are both very important for cell therapies. Royal jelly (RJ) is a nutritional substance produced by worker bees that contains a substantial amounts of proteins that are beneficial for cell growth and proliferation. RJ is widely used in traditional medicine today, and due to the specific components in its content, it has been reported to have antioxidant, antiproliferative, antimicrobial, neuroprotective, anti-inflammatory, immunomodulatory and anti-ageing properties. In our study, human Wharton's jelly mesenchymal stem cells (WJ-MSCs) derived from umbilical cord matrix were grown in culture medium supplemented with RJ. The control group comprised minimum essential medium (MEM) and 10% foetal bovine serum (FBS); RJ groups were formed using MEM, 10% FBS and 0.075mg/ml or 0.150mg/ml RJ. In our study, we evaluated the effect of RJ on WJ-MSC growth by MTT assay, proliferating cell nuclear antigen ELISA, β-galactosidase activity assay, MitoTracker Green staining and differentiation tests in adipogenic, osteogenic and chondrogenic cell lines. It was observed that the number of mitochondria increased, senescence decreased and osteogenic differentiation increased after differentiation induction after the addition of RJ to MSC culture. In general, the results of this study indicate that WJ-MSCs enhance mitochondrial numbers and important cellular activities, such as antisenescence and osteogenic differentiation, and with increasing evidence from further studies, RJ supplementation may be found beneficial for the use of MSCs in bone engineering regenerative medicine or cell therapy.

The Effect of Royal Jelly on Irisin in Experimentally Diabetic Rats

Diabetes Mellitus (DM) is considered a very common health problem today. It causes many acute and chronic complications and negatively affects the quality of life of patients. It is known that diabetes has an impact on many biochemical processes. This study aimed to evaluate the interaction between royal jelly (RJ) and diabetes with irisin, a parameter that has not been investigated before. The study was planned with 3 groups: control group, DM group, DM+350 mg/kg RJ group. In the experiments, 18 female Wistar albino rats were studied. Irisin levels in rat blood serum were determined using the ELISA (Enzyme-Linked Immuno Sorbent Assay) method. Glucose levels in blood taken from the tail vein were determined with a glucometer. As a result of the experimental study, a statistically significant difference was found in the DM+350 mg/kg RJ group compared to the control group (p

The Effect of Royal Jelly on Telomere Length and Some Biochemical Parameters in Wistar Albino Rats with Liver Damage Caused by Carbon Tetrachloride.

Royal jelly (RJ) is a natural bee product that has been used for therapeutic purposes since ancient times. The therapeutic properties of this product, which has rich biological content, are still being investigated with new approaches. In this study, the effect of RJ on telomere length, some antioxidant parameters, and lipid profile was examined. This study will contribute to the literature as it is the first to evaluate the effect of RJ on the length of telomeres in damaged liver tissues. In the study, the levels of serum triglyceride, total cholesterol (TC), high-density lipoprotein cholesterol, low-density lipoprotein cholesterol (LDL-C), aspartate transaminase (AST), alanine transaminase (ALT), telomerase, 8'-hydroxy-2'-deoxyguanosine (8-OHdG), and paraoxonase-1 (PON1) were investigated with enzyme-linked immunosorbent assay method and telomere lengths were investigated by real-time quantitative polymerase chain reaction. The increased TC, LDL-C levels, and AST and ALT activities in the serum after carbon tetrachloride (CCl4) administration approached the control level after RJ administration. PON1 activity decreased in groups with CCl4. PON1 activity increased after RJ administration. The level of 8-OHdG, which increased groups with CCl4, decreased after RJ administration. According to the results of telomere length analysis in liver tissues, telomere lengths in damaged tissues were significantly shortened with CCl4 application and increased with RJ application. Based on the findings of the study, it was concluded that RJ may have therapeutic effects on telomere lengths and some biochemistry parameters.

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.

Royal Jelly (Apis mellifera) As an Antimicrobial Activity Inhibition

Royal jelly (RJ) has lots of compounds such as protein, vitamins, and a variety of bioactive compounds (10-hydroxy-2-decanoic or 10-HDA acids). 10-HDA is a lipid fraction component in RJ content with antibacterial and immunomodulatory activity. RJ proteins that have antimicrobial, antifungal, anti-tumor, antidiabetic, and antihypertensive properties. The authors continue their research about the effect of RJ on the inhibitory strength of the given antibacterial activity. L. monocytogenes, S. aureus, and E. coli were among the microbes studied in this research. This study used an experimental method with a complete randomized design (CRD) of 5 treatments and 4 replications, if the treatment showed a noticeable effect (P<0.05) then Duncan’s multiple distance test was continued. According to the findings of this study, the royal jelly variations given had a significant inhibitory effect on antibacterial activity. The inhibitory ability of L. monocytogenes proved that the second treatment had a higher inhibitory power of 30.94±25.786b, in S. aureus, the second treatment gave a moderate inhibitory power of 9.013±1.841a, and in E. coli, the second treatment gave a weak inhibitory power of 3.24±3.748a. The conclusion of studies showed royal jelly with dilution variety could be antimicrobial agent and to be strongest inhibitor in L. monocytogenes and lowest in E. coli. The suggestion of studies needs management in the isolates of bacteria available and should be estimated before we do the research about antimicrobial activity inhibitors.

Arı Sütünün Tüketici Egzersize Bağlı Oksidatif Stres Üzerindeki Rolü

In this study, the effects of Royal Jelly (RJ) on oxidative stress caused by exhaustive swimming exercise in rat tissues were evaluated. Methods: Twenty four male Wistar albino rats were indiscriminately distributed into four experimental groups: Sedentary control (SC); SC with administration of RJ (100 mg kg-1) (SC + RJ); exhaustive swimming exercise (E); Exhaustive swimming exercise with administration of RJ (100 mg kg-1) (E + RJ). 100 mg kg-1 of RJ were dissolved in drinking water. Rats in the SC+RJ and E+RJ groups supplemented with RJ (100 mg kg-1) orally once a day for two weeks. Rats in groups E and E+RJ subjected to acute exhaustive swimming exercise on the 14th day of the study, then some biochemical parameters related to oxidative stress of all groups were measured. Results: The activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), blood urea nitrogen (BUN) and creatinine (CRE) levels significantly raised in the exercised rats compared with the sedentary rats (P < 0.05). The decreased superoxide dismutase (SOD), glutathione peroxidase (GSHPx), and catalase (CAT) activities of muscular and hepatic tissues significantly increased and the high malondialdehyde (MDA) levels of muscular, hepatic and kidney tissues significantly reduced in exercised rats treated with RJ (P < 0.05). Conclucion: Collectively, in this study, protective effects of RJ on tissues against oxidative damage after exhaustive exercise were observed.

Effects of Royal Jelly on Gut Dysbiosis and NAFLD in db/db Mice.

Royal jelly (RJ) is a naturally occurring substance synthesized by honeybees and has various health benefits. Herein, we focused on the medium-chain fatty acids (MCFAs) unique to RJ and evaluated their therapeutic efficacy in treating non-alcoholic fatty liver disease (NAFLD). We examined db/m mice that were exclusively fed a normal diet, db/db mice exclusively fed a normal diet, and db/db mice fed varying RJ quantities (0.2, 1, and 5%). RJ improved NAFLD activity scores and decreased gene expression related to fatty acid metabolism, fibrosis, and inflammation in the liver. RJ regulated innate immunity-related inflammatory responses in the small intestine and decreased the expression of genes associated with inflammation and nutrient absorption transporters. RJ increased the number of operational taxonomic units, the abundance of Bacteroides, and seven taxa, including bacteria that produce short-chain fatty acids. RJ increased the concentrations of RJ-related MCFAs (10-hidroxy-2-decenoic acid, 10-hydroxydecanoic acid, 2-decenedioic acid, and sebacic acid) in the serum and liver. These RJ-related MCFAs decreased saturated fatty acid deposition in HepG2 cells and decreased the gene expression associated with fibrosis and fatty acid metabolism. RJ and RJ-related MCFAs improved dysbiosis and regulated the expression of inflammation-, fibrosis-, and nutrient absorption transporter-related genes, thereby preventing NAFLD.

Royal jelly extracellular vesicles promote wound healing by modulating underlying cellular responses

Apis mellifera royal jelly (RJ) is a well-known remedy in traditional medicine around the world and its versatile effects range from antibacterial to anti-inflammatory properties and pro-regenerative properties. As a glandular product, RJ has been shown to contain a substantial number of extracellular vesicles (EVs), and, in this study, we aimed to investigate the extent of involvement of RJEVs in wound healing-associated effects. Molecular analysis of RJEVs verified the presence of exosomal markers such as CD63 and syntenin, and cargo molecules MRJP1, defensin-1, and jellein-3. Furthermore, RJEVs were demonstrated to modulate mesenchymal stem cell (MSC) differentiation and secretome, as well as decrease LPS-induced inflammation in macrophages by blocking the mitogen-activatedprotein kinase (MAPK) pathway. Invivo studies confirmed antibacterial effects of RJEVs and demonstrated an acceleration of wound healing in a splinted mouse model. This study suggests that RJEVs play a crucial role in the known effects of RJ by modulating the inflammatory phase and cellular response in wound healing. Transfer of RJ into the clinics has been impeded by the high complexity of the raw material. Isolating EVs from the raw RJ decreases the complexity while allowing standardization and quality control, bringing a natural nano-therapy one step closer to the clinics.

Inhibition of Skin Pathogenic Bacteria, Antioxidant and Anti-Inflammatory Activity of Royal Jelly from Northern Thailand.

Royal jelly is a nutritious substance produced by the hypopharyngeal and mandibular glands of honeybees. Royal jelly possesses many attractive and beneficial properties which make it an ideal component in medical and pharmaceutical products. The antibacterial, antioxidant, and anti-inflammatory activities of royal jelly from honeybees (Apis mellifera) were determined in this study. Moreover, the total phenolic and flavonoid contents of the royal jelly were also evaluated. The effects of royal jelly on growth inhibition against skin pathogenic bacteria, including Cutibacterium acnes, methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus epidermidis, and Corynebacterium spp., were investigated by the agar well diffusion method. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were further determined by the broth dilution method. The results indicated that royal jelly showed antibacterial activity by inhibiting the growth of Gram-positive pathogenic bacteria, while the effectiveness decreased against Gram-negative bacteria. Interestingly, royal jelly from Lamphun (RJ-LP1), and Chiang Mai (RJ-CM1), presented high inhibitory efficacy against C. acnes, MRSA, and S. aureus within 4 h by a time killing assay. Furthermore, the anti-inflammatory properties of royal jelly were tested using RAW264.7 macrophage cells, and results revealed that RJ-LP1 and RJ-CM1 could reduce nitric oxide (NO) production and suppress iNOS gene expression. After testing the antioxidant activity, RJ-CM1 and RJ-CM2 of royal jelly from Chiang Mai had the highest level. Additionally, RJ-CM1 also showed the highest total phenolic and flavonoid content. These findings have brought forward new knowledge of the antibacterial, antioxidant, and anti-inflammatory properties of royal jelly, which will improve clinical and pharmaceutical uses of royal jelly as an alternative therapy for bacterial infections, and also as a dietary supplement product.

Effect of Royal Jelly on Gene Expression of Toll-like Receptors 1-9 in Patients with Hepatitis B.

By damaging the liver, hepatitis B can result in acute and chronic diseases, such as cirrhosis or hepatocellular carcinoma. Viable treatments for such diseases using natural products and determinative biomarkers have been proposed but require evaluation to improve their effects. Therefore, this study aims to examine how effectively a specific natural product (namely, royal jelly) protects the body from the copy number of the virus, as well as TLR1 to TLR9 gene expressions. The effectiveness of royal jelly was tested by giving it (orally) to 30 hepatitis B patients for one month. HBV copy number and mRNA levels of TLRs were explored using Real Time PCR technique, and liver enzymes were evaluated too. Orally treatment with royal jelly led to a significant decrease in HBV-DNA copy number, down-regulation of TLR2 and TLR8, and up-regulation of TLR3. However, mRNA levels of the TLRs were not altered in the female, while TLR1, TLR2, and TLR5 were significantly decreased in the male participants. It seems that royal jelly has anti-viral and anti-inflammatory roles in the in vivo conditions in a dependent manner in TLR3, TLR2, and TLR8. Therefore, it can be suggested as a safe complementary agent for patients with hepatitis B.

Arı sütünün obezite üzerine etkileri

Obesity is a disease that affects people's quality of life and is a risk factor for some fatal diseases. Its prevalence is increasing in the world and the biggest factor is nutritional problems and a sedentary lifestyle. Royal jelly (RJ), a natural product for obesity, a preventable disease, has been the subject of various studies. RJ secreted by young honey bees (worker bees) is the only food source for the queen bee and the first three days of food for immature bees. Several studies have shown RJ's anti-obesity, antioxidant, anticarcinogenic, antimicrobial, and anti-inflammatory activities. In addition, RJ is seen as a promising functional food in the prevention of obesity and protection from its negative effects. This study is an examination of studies on the effects of RJ on obesity and its accompanying problems.

Front Cover: Dose‐Dependent Effects of Royal Jelly on Estrogen‐ and Progesterone‐Induced Mammary Gland Hyperplasia in Rats

Mol. Nutr. Food Res. 2022, 66, 202100355 DOI: 10.1002/mnfr.202100355 Royal jelly (RJ) is obtained from honeybee queen cells. In article number 2100355, Liu and co-workers used RJ on hyperplasia of the mammary gland (HMG) in rats. RJ is demonstrated to participate in regulating the hypothalamus-pituitary-ovarian axis, subside endocrine dyscrasia induced by estrogen and progesterone, and alleviate the hyperplasia of breast tissue, implying great potential in the prevention and treatment of HMG.

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

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

Effect of oral intake of royal jelly on endothelium function in hemodialysis patients: study protocol for multicenter, double-blind, randomized control trial

BackgroundHemodialysis (HD) is a common renal replacement therapy for patients with renal failure. Cardiovascular and cerebrovascular diseases are known to shorten survival periods and worsen the quality of life of HD patients. Atherosclerosis is a major cause of vascular diseases, and various factors such as abnormality of lipid metabolism and increased macrophage activity, oxidative stress, and endothelial dysfunction are associated with its pathogenesis and progression. Further, endothelial stem cells (ESCs) have been reported to play important roles in endothelial functions. Royal jelly (RJ) affects atherosclerosis- and endothelial function-related factors. The main aim of this trial is to investigate whether oral intake of RJ can maintain endothelial function in HD patients. In addition, the effects of RJ intake on atherosclerosis, ESC count, inflammation, and oxidative stress will be analyzed.MethodsThis will be a multicenter, prospective, double-blind, randomized controlled trial. We will enroll 270 participants at Nagasaki Jin Hospital, Shinzato Clinic Urakami, and Maeda Clinic, Japan. The participants will be randomized into RJ and placebo groups. The trial will be conducted according to the principles of the Declaration of Helsinki, and all participants will be required to provide written informed consent. The RJ group will be treated with 3600 mg/day of RJ for 24 months, and the placebo group will be treated with starch for 24 months. The primary endpoint will be the change in flow-mediated dilation (FMD), a parameter of endothelium function, from the time before treatment initiation to 24 months after treatment initiation. The secondary and other endpoints will be changes in FMD; ESC count; serum levels of vascular endothelial cell growth factor, macrophage colony-stimulating factor, 8-hydroxydeoxyguanosine, and malondialdehyde; the incidence of cardiovascular diseases, cerebrovascular diseases, and stenosis of blood access; and safety.DiscussionThis trial will clarify whether oral intake of RJ can maintain endothelial function and suppress the progression of atherosclerosis in HD patients. In addition, it will clarify the effects of RJ on ESCs, oxidative stress, and angiogenic activity in blood samples.Trial registrationThe Japan Registry of Clinical Trials jRCTs071200031. Registered on 7 December 2020.

Neurogenesis in the rat neonate's hippocampus with maternal short-term REM sleep deprivation restores by royal jelly treatment.

BackgroundNumerous studies have shown the effects of rapid eye movement sleep deprivation (REM‐SD) on behavior and brain structures. The impact of REM‐SD on learning and memory, thus neurogenesis, has been reported in previous studies. Royal jelly (RJ) is known as the wealthiest biological nutrient with various physiological properties. This study aimed to study the possible effect of RJ on neurogenesis of the rat hippocampus neonates following exposure of mother to REM‐SD during pregnancy.MethodsThirty neonate rats from 15 pregnant Wistar rats were used. To induce REM‐SD, the flowerpot method was used. The pregnant rats were divided into five groups (n = 3): group 1, no treatment; group 2, REM‐SD; groups 3, 4, and 5, REM‐SD +RJ. The former group received 72 h REM‐SD during pregnancy (days 7, 14, 21), and the latter group received REM‐SD + RJ (three trial groups). At week 4, the rat neonates of all groups were sacrificed (n = 6 each group). Their brains were fixed, removed, and prepared for Nissl and Hoechst 33342 staining. By using real time polymerase chain reaction methode the brain‐derived neurotrophic factor BDNF gene expression was studied (RT‐PCR), brain‐derived neurotrophic factor (BDNF) gene expression was studied. The results were analyzed statistically, and the Pv < .05 was considered significant.ResultsThe results showed a significant decrease in the number of neurons in the hippocampus of neonatal rats of REM‐SD mothers compared to the neonates of the mother with REM‐SD + RJ. REM‐SD also led to an increase in apoptosis reaching the neonates from the REM‐SD + RJ animals. High expression of BDNF was observed in the hippocampus of the neonates from REM‐SD + RJ treated mothers.ConclusionRJ acts as a neuroprotective agent that could compensate for the effects of REM‐SD on learning and memory via restoring neurogenesis.

Protective Effect of Royal Jelly on Sperm Parameters, In-vitro Fertilizing Potential, and Oxidative Stress Indicators in the Testis of Mice Exposed to Ethephon

Protective Effect of Royal Jelly on Sperm Parameters, In-vitro Fertilizing Potential, and Oxidative Stress Indicators in the Testis of Mice Exposed to Ethephon

A Randomized, Double-Blind Comparison Study of Royal Jelly to Augment Vascular Endothelial Function in Healthy Volunteers.

Aims: Royal jelly, a creamy substance secreted by honeybees, has been reported to have beneficial effects against dyslipidemia and metabolic syndrome. However, the effects of royal jelly on atherogenesis remain unknown. Hence, we prospectively evaluated whether royal jelly augments vascular endothelial function, which can reflect early atherogenesis, in healthy volunteers. Methods: This was a single-center, double-blind, 1:1 randomized placebo-controlled study conducted from October 2018 to December 2019. A total of 100 healthy volunteers were randomly assigned to receive either royal jelly 690 mg or placebo daily for 4 weeks. The primary endpoint was augmentation in vascular endothelial function as assessed using the change in the reactive hyperemia peripheral arterial tonometry index (RH-PAT) index, and the secondary endpoints were the changes in liver function and lipid profiles between baseline and 4 weeks after enrollment. Results: The mean age of the participants was 35.0±9.3 years in the placebo group and 36.1±9.1 years in the royal jelly groups; 45% and 50% of the placebo and the royal jelly groups, respectively, were male. The percentage relative change in the RH-PAT index was significantly higher in the royal jelly group than in the placebo group (21.4%±53.1% vs. 0.05%±40.9%,P=0.037). The percentage relative changes in alanine aminotransferase and γ-glutamyl transpeptidase were significantly lower in the royal jelly group than in the placebo group (alanine aminotransferase: −6.06%±22.2% vs. 11.6%±46.5%,P=0.02; γ-glutamyl transpeptidase: −3.45%±17.8% vs. 4.62%±19.4%,P=0.045). Lipid profiles were not significantly different between the two groups. Conclusions: Royal jelly might have antiatherogenic property by improving vascular endothelial function. It also augmented liver functions in healthy volunteers.