Royal Jelly Peptides Inhibit Lipid Peroxidation In Vitro and In Vivo

Antioxidant and Anti-Inflammatory Properties of Hydrolyzed Royal Jelly Peptide in Human Dermal Fibroblasts: Implications for Skin Health and Care Applications

Hydrolyzed royal jelly peptide (RJP) has garnered attention for its health-promoting functions. However, the potential applications of RJP in skincare have not been fully explored. In this study, we prepared RJP through the enzymatic hydrolysis of royal jelly protein with trypsin and investigated its antioxidant and anti-inflammatory properties on primary human dermal fibroblasts (HDFs). Our results demonstrate that RJP effectively inhibits oxidative damage induced by H2O2 and lipid peroxidation triggered by AAPH and t-BuOOH in HDFs. This effect may be attributed to the ability of RJP to enhance the level of glutathione and the activities of catalase and glutathione peroxidase 4, as well as its excellent iron chelating capacity. Furthermore, RJP modulates the NLRP3 inflammasome-mediated inflammatory response in HDFs, suppressing the mRNA expressions of NLRP3 and IL-1β in the primer stage induced by LPS and the release of mature IL-1β induced by ATP, monosodium urate, or nigericin in the activation stage. RJP also represses the expressions of COX2 and iNOS induced by LPS. Finally, we reveal that RJP exhibits superior antioxidant and anti-inflammatory properties over unhydrolyzed royal jelly protein. These findings suggest that RJP exerts protective effects on skin cells through antioxidative and anti-inflammatory mechanisms, indicating its promise for potential therapeutic avenues for managing oxidative stress and inflammation-related skin disorders.

Activation of AMPK Entails the Protective Effect of Royal Jelly against High-Fat-Diet-Induced Hyperglycemia, Hyperlipidemia, and Non-Alcoholic Fatty Liver Disease in Rats

This study examined the mechanism underlying the protective effect of royal jelly (RJ) against high-fat-diet (HFD)-mediated non-alcoholic liver disease (NAFLD) in rats. Adult male rats were divided into five groups (n = 8 each): control fed a standard diet, control + RJ (300 mg/kg), HFD, HFD + RJ (300 mg/kg), and HFD + RJ + CC (0.2 mg/kg). The treatment with RJ reduced weight gain, increased fat pads, and attenuated fasting hyperglycemia, hyperinsulinemia, and glucose tolerance in the HFD-fed rats. It also reduced the serum levels of liver function enzymes, interleukin 6 (IL-6), tumor necrosis factor-α (TNF-α), and leptin but significantly increased the serum levels of adiponectin. In addition, and with no effect on lipid excretion in stool, RJ significantly decreased the hepatic mRNA expression of SREBP1, serum, hepatic cholesterol, and triglycerides but increased hepatic mRNA levels of PPARα. Furthermore, RJ reduced the hepatic levels of TNF-α, IL-6, and malondialdehyde (MDA) in the livers of these rats. Of note, with no effect on the mRNA levels of AMPK, RJ stimulated the phosphorylation of AMPK and increased the levels of superoxide dismutase (SOD) and total glutathione (GSH) in the livers of the control and HFD-fed rats. In conclusion, RJ attenuates NAFLD via its antioxidant potential and adiponectin-independent activation of liver AMPK.

The role of microencapsulation in maintaining biological activity of royal jelly: comparison with biological activity and bioaccessibility of microencapsulated, fresh and lyophilized forms during storage

BACKGROUND

Royal jelly (RJ) is a unique beehive product and has been recommended for human health since ancient times because of its antioxidant, antimicrobial, antiproliferative, neuroprotective, anti-lipidemic and anti-aging features. However, the biggest obstacle in the use of RJ is the need for cold storage and the instability of bioactive components over time. In the present study, 10-hydroxy-2-decenoic acid (10-HDA) content, as well as antioxidant [using 1,1-diphenyl-2-picrylhydrazy and 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) methods] and antimicrobial activity (five Gram-positive, five Gram-negative and three yeasts), were comparatively evaluated for three RJ forms, two of which can be stored at 24 ± 1 °C during storage.

RESULTS

Microencapsulated royal jelly (MRJ) stored at room temperature succeeded in preserving its 10-HDA content, a major bioactive compound, during the 6 months, with respect to lyophilized royal jelly (LRJ) and fresh RJ stored at 4 °C. The initial 10-HDA contents of RJ, LRJ and MRJ were determined as 1.90%, 5.26% and 2.75%, respectively. Moreover, the total phenolic content, antioxidant capacity and antimicrobial activity mostly remained constant throughout the storage period (P ≥ 0.05). Gram-positive strains were generally more sensitive than Gram-negative strains. In the present study, the in vitro simulated digestion analysis showed that MRJ can tolerate the digestion process.

CONCLUSION

Overall, the encapsulation process was considered as one preservative technique for RJ. The microencapsulation of RJ as shown in the results of the present study are encouraging in terms of enabling the local beekeeping sector to achieve ease of production and increased product diversity. MRJ shows promise as a commercial product with a high export value for producers. © 2022 Society of Chemical Industry.

Protective potential of royal jelly against hydroxyurea -induced hepatic injury in rats via antioxidant, anti-inflammatory, and anti-apoptosis properties

Hydroxyurea (HDU) is a widely used medication for various malignancies, thalassemia, and sickle cell anemia with reported side effects. The current study investigated HDU- induced hepatic injury and the protective potential of the royal jelly (RJ) against this hepatotoxic effect in the light of hepatic oxidative/ antioxidative status, pro-inflammatory cytokine, apoptosis signaling pathway, and histopathology. Sixty albino rats were used (n = 10/group) for 60 days: control, RJ (100 mg/kg body weight, orally), HDU (225 mg/kg body weight, orally), 2HDU (450 mg/kg body weight, orally), and HDU + RJ groups. HDU-treated rats showed significant elevation of liver function tests as aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase, as well as malondialdehyde and nitric oxide (oxidative biomarkers) and significant decreased hepatic antioxidant molecules (reduced glutathione, superoxide dismutase, and glutathione peroxidase), compared to a control group, that more pronounced in the high dose of HDU. In addition, HDU induced significant upregulation of TNF-α and the Caspase-3 apoptotic pathway. Moreover, the liver of HDU treated groups showed various hepatic lesions from mild to severe necrotic changes related to the HDU dose. However, administration of RJ with HDU improved liver function tests, liver histology, and hepatic oxidative/antioxidative status concerning HDU groups. Furthermore, oral RJ administration with HDU significantly lessens the immune-expression area % of TNF-α and Caspase-3. Thus, the royal jelly has antioxidant, anti-inflammatory, and anti-apoptotic properties against HDU- induced hepatic injury and could be, therefore, used as adjuvant therapy in patients with long-term HDU medication.

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.

Effects of honeycomb extract on the growth performance, carcass traits, immunity, antioxidant function and intestinal microorganisms of yellow bantam broilers

Although many studies have already described the physiological effects of bee products, such as honey, propolis, pollen, and royal jelly, on livestock farming, the health benefits of the honeycomb are still not fully understood. The problem of drug residues and bacterial resistance caused by the abuse of antibiotics is becoming increasingly serious. For this reason, a safe, green substitute has to be sought. We conducted a comparative study of honeycomb extract (HE) and an antibiotic on growth performance, carcass traits, immunity, antioxidant function and intestinal microorganisms of yellow bantam broilers. A total of four hundred eighty 21-day-old female yellow bantam broilers were randomly divided into 5 groups of 6 replicates of 16 birds each. The 5 groups were as follows, with birds receiving a basal diet supplemented with 150 ppm (mg/kg) of chlortetracycline (CTE), a basal diet without HE (control group), and a basal diet with 0.1%, 0.15%, or 0.2% HE for 60 days. The results showed that HE addition significantly increased average daily feed intake (ADFI), average daily gain (ADG), decrease feed gain ratio (F/G) from 21 to 80 and 51 to 80 days of age compared to the control group, with all 3 HE addition groups having statistically identical values to the antibiotic group. HE implementation dramatically increased spleen index, serum immunoglobulin A (IgA), immunoglobulin M (IgM,), glutathione peroxide (GSH-Px), superoxide dismutase (SOD), total antioxidant capacity (T-AOC), and total cecum bacteria and Lactobacillus compared to the control group, numerically at the same level as, or even better than, the antibiotic group. HE and CTE both markly reduced serum malondialdehyde (MDA) concentration compared to the control group, with higher concentrations of HE reducing the effect more dramatically than antibiotics. Both HE and CTE significantly raised dressed yield compared to the control group. In summary, HE, as a potential antibiotic alternative, improved growth performance, carcass traits, immune function, serum antioxidant capacity and intestinal microorganisms in yellow bantam broilers. According to the cubic regression analyses, the recommended supplemental dose of HE was calculated to be 0.15 to 0.17% for female yellow bantam broilers between 21 and 80 d of age.

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.

Royal jelly enhanced the antioxidant activities and modulated the gut microbiota in healthy mice

Royal jelly (RJ) is a well-known traditional health food that has a wide range of pharmacological activities. In this study, mice were fed with different doses of RJ for 30 days and their antioxidant activities and gut microbiota were measured to examine the correlation between gut microbiota and overall health. RJ did not influence the feed consumption or relative organ weight, but RJ did increase the amount of serum interleukin 10 (IL-10), as well as the levels of antioxidant activities in the liver and kidney. The middle dose of RJ (RJM) decreased the relative abundance of Proteobacteria at phylum level, increased the relative abundance of Lachnospiraceae_NK4A136_group and Bacteroides. Correlation analysis indicated that RJ could optimize the functional network of gut microbiota and the interactions between the gut microbiota and the host. In conclusion, RJ could enhance the antioxidant activities and modulate the gut microbiota. RJM treatment had a more positive effect on physical health compared with RJL and RJH treatments. PRACTICAL APPLICATIONS: Royal jelly is a healthy dietary supplement which has a wide range of functions. The research helps us know the action mechanism of RJ in healthy body and analyzed the correlation of gut microbiota and physiological state. The appropriate dose of RJ was also studied and the health functions of RJ for healthy body were proved. This research could help to increase the RJ consuming in market.

Improving Reproductive Performance and Health of Mammals Using Honeybee Products

Honeybee products have positive effects on the reproductive performance of mammals. Many honeybee product constituents are biologically active, with antioxidant, antimicrobial, antiviral, anti-inflammatory, immunomodulatory, antifungal, wound-healing, and cardio-protective properties. Honeybee products also improve male and female fertility rates by enhancing gamete cryopreservation, in vitro maturation and fertilization, and embryo development. Previously published studies confirmed their efficacy for alleviating reproductive toxicity caused by contaminants and lifestyle habits that impair overall health and well-being. However, high-dose oral administration of honeybee products may adversely affect the reproductive system, and unfavorable effects were alleviated by treatment cessation. For this reason, this review proposes that bioactive components from bee products can be used as a strategy for improving the reproductive performance and health of mammals.

Adaptogenic potential of royal jelly in reproductive system of heat stress-exposed male rats

Testicular heat stress (HS) can lead to testicular tissue destruction and spermatogenesis disturbances. Royal Jelly (RJ) has been introduced as a potent antioxidant. We investigated the effects of RJ on testicular tissue, oxidative stress and sperm apoptosis in HS-exposed rats. Compared to HS-exposed groups, RJ co-treatment could improve testosterone reduction and histopathological damages. The RJ co-administration decreased MDA level in testicular tissue, while TAC and CAT levels were remarkably increased compared to HS-exposed groups. Moreover, significant higher expression level of Bcl-2 and lower expression levels of P53 and Caspase-3 were seen following RJ co-administration compared to HS-exposed groups. Our data suggest that RJ can effectively ameliorate experimental HS-induced testiculopathies in rats through testicular antioxidant defense system restoration and germ cells apoptosis regulation.

Royal jelly may improve sperm characteristics during preservation of rooster semen: Gene expression of antioxidant enzymes

Sustainable production and the increasing number of embryonated hatching eggs are critical aspects of the poultry production industry. The present paper aims to appraise the effectiveness of royal jelly (RJ) on the semen characteristics of Native Mazandaran roosters in both liquid and frozen storage conditions. Semen collected from 10 sexually mature roosters and following dilution was supplemented with RJ at 0.0 (control), 5 (RJ5), 10 (RJ10), 20 (RJ20) and 40 (RJ 40) mg/ml. After cooling and freezing-thawing, the percentage of forward progressive motility, viability, abnormality, hypo-osmotic swelling test (HOST) and the mRNA abundance of antioxidant enzymes of spermatozoa were measured. Our results revealed that the addition of 5 mg/ml RJ to the semen extender significantly increased (p < .05) the percentages of forward progressive motility, viability and HOST during liquid and frozen storage. The abnormality of spermatozoa in the RJ5 group was significantly lower compared to the other groups. During liquid storage, a significant decrease in forward progressive motility was found after 48 hr in comparison with 24 hr at 4°C. High levels of RJ (from 10 to 40 mg/ml) were severely decreased the characteristics of rooster spermatozoa in comparison with RJ5 and the control group. The inclusion of RJ at 5 mg/ml to the semen extender enhanced the mRNA transcript of antioxidant enzymes of spermatozoa during liquid preservation. The mRNA abundance of antioxidant enzymes did not influence by cryostorage. Overall, these data suggest that supplementation of RJ at 5 mg/ml to the extender improved semen characteristics and redox status of rooster spermatozoa.

The Carboxyl-Terminal Penta-Peptide Repeats of Major Royal Jelly Protein 3 Enhance Cell Proliferation

Royal jelly (RJ) is known as an important functional foodstuff that promotes several health benefits and contains various bioactive substances, including major royal jelly proteins (MRJPs). Among the MRJPs, MRJP3 possesses both cell proliferation and wound healing effects. As the carboxyl domain of MRJP3 contains tandem penta-peptide repeat (TPR) sequences unique to MRJP3 among the MRJPs, we purified the TPRs as glutathione-S-transferase (GST)-fusion proteins and demonstrated their dose-dependent effects on THP-1 and Vero cell proliferation. The GST-TPR protein with 19 repeats (GST-TPR19) showed cell proliferative activity equivalent to MRJP3 and higher than GST-TPR6. GST-TPR19 also exhibited wound healing activity at a level similar to MRJP3. Digestion of GST-TPR19 with trypsin had no effect on its cell proliferative activity, suggesting that the main digested products; i.e., penta-peptides (Q-N-x-N-[K/R]), maintain the cell proliferative ability of MRJP3. In conclusion, the TPRs of MRJP3 are critical to the beneficial effect(s) of RJ.

Royal jelly attenuates metabolic defects in a Drosophila mutant with elevated TORC1 activity

Target of rapamycin complex 1 (TORC1) is a master regulator of cell metabolism, and its dysregulation has been linked to an array of pathologies, including cancer and age-related diseases. Nprl3, a component of GTPase-activating protein towards Rags complex 1 (GATOR1), inhibits TORC1 activity under nutrient scarcity status. The nprl3 mutant exhibits some metabolic defects due to hyper TORC1 activity in Drosophila Royal jelly (RJ) is a honeybee-secreted product and plays an essential role in caste differentiation that requires TORC1 activity. RJ is also used as a health-benefit food for its potential roles on antioxidant and anti-aging. In this study, nprl3-mutant flies were used to measure the effect of RJ on metabolic modulation. Interestingly, RJ feeding significantly increased survival and decreased TORC1 activity in the nprl3 mutant. RJ feeding also ameliorated the abnormal reactive oxygen species (ROS) levels and energy status in the nprl3 mutant. The proteins in RJ were characterized to be the essential components in increasing nprl3 mutant viability. These findings suggest that RJ modulates some metabolic defects associated with elevated TORC1 activity and that the nprl3-mutant fly might be a useful tool for investigating the bioactive components of RJ in vivo.

Oral administration of royal jelly may improve the preservation of rooster spermatozoa

The aim of the present study was to investigate the effect of dietary supplementation of royal jelly (RJ) on liquid and frozen storage of rooster spermatozoa. Twenty-five 30-week-old of Mazandaran native breeder roosters were randomly divided into five treatments (n = 5 roosters/group). Experimental treatments are designed to include a control group and various levels (0.0 (RJ0), 100 (RJ100), 200 (RJ200), 300 (RJ300) mg kg^-1  BW^-1 ) of royal jelly (RJ) that were fed to the roosters using force-feed method. The percentage of forward progressive motility, abnormal spermatozoa, membrane integrity and viability of spermatozoa evaluated after 24 and 48 hr of cooling (at 4°C) and after the freeze-thawing process. Also, mitochondrial activity and DNA fragmentation in fresh (24 hr) and post-thawed spermatozoa were assessed. The result of this study showed that the spermatozoa forward progressive motility, abnormality, membrane integrity, and viability were improved by the RJ100 group compared to the other groups after 24 and 48 hr storage period at 4°C. The percentage of membrane integrity and forward progressive motility after freeze-thawing in the RJ100 group was significantly higher than the other groups, and the percentage of abnormal spermatozoa was lower. A significant decrease in semen quality parameters was seen after 24 and 48 hr of refrigeration, but there was no observed change between 2 and 24 hr in the RJ100. The viability percentage of spermatozoa in both RJ100 and RJ200 groups was not different. Moreover, after freeze-thawing, DNA integrity and mitochondrial activity in the RJ100 group were significantly higher than the other groups. According to our results, feeding of RJ at 100 mg kg^-1  BW^-1 to the roosters was improved spermatozoa characteristics during liquid and cryopreservation conditions.

Comprehensive evaluation of radical scavenging, reducing power and chelating capacity of free proteinogenic amino acids using spectroscopic assays and multivariate exploratory techniques

Among others, amino acids can inhibit oxidative processes through multiple pathways including inactivation of reactive oxygen species, scavenging free radicals, chelation of pro-oxidative transition metals, as well as reduction of hydroperoxides. Moreover, they can be a major target for oxidants as a result of their abundance in biological systems. The purpose of the present study is to examine the radical scavenging, reducing power and chelating capacity of the free proteinogenic amino acids, using several analytical assays based on different mechanisms and monitored via molecular UV-vis absorption spectrophotometry. In most of the assays, the highest antioxidant activity is rendered by Cys and Trp, known for their involvement in physiological radical reactions, followed by Tyr, Asn and Arg. The least reactive amino acids with respect to both radical scavenging and reducing power principle were Ala, Met, Thr and Val. The hierarchy of the amino acids based on their antioxidant activity is shifting, depending on the analytical assay employed. Results from the multivariate exploratory techniques-hierarchical cluster analysis and principal component analysis-could point out the methods that are most similar and best connected to each other, thus classifying the investigated amino acids according to their activity. Considering the results of chemometric techniques, the antioxidant methods that best discriminate between amino acids are DPPH bleaching and SORS assays. Not only the comprehensive study of antioxidant activity of amino acids is novel in this study but also the application of the sum of ranking differences to compare and rank the various antioxidant capacity assays. The obtained results will support the development of amino acids based multifunctional formulations with important physiologically relevant implications for both humans and animals, with a possible future use in the food industry.

Involvement of Mfn2, Bcl2/Bax signaling and mitochondrial viability in the potential protective effect of Royal jelly against mitochondria-mediated ovarian apoptosis by cisplatin in rats

OBJECTIVES

The current study aimed to assess cisplatin-mediated ovarian apoptosis in a rat model by Royal jelly (RJ).

MATERIALS AND METHODS

Thirty female adult albino rats (180-200 g) were divided into three groups (n=10): saline (0.9% NaCl, IP) was given to the control group, the cisplatin group: received (5 mg/kg/once a week IP) for 5 successive weeks, the RJ+Cis. group: received RJ (100 mg/kg/ day PO daily), and Cisplatin (5 mg/kg/once per week IP) for 5 successive weeks. At the end of the experiment, rats were sacrificed and their ovaries were isolated and used for biochemical analysis, molecular investigations and morphometric assessment as well as histological study. Moreover, blood samples were collected for determination of follicle-stimulating hormone (FSH), luteinizing hormone (LH), Estradiol, progesterone and anti-mullerian hormone (AMH).

RESULTS

The current study clarified that RJ given to rats prior to cisplatin significantly increased the ovarian and uterine weights, in addition to follicular count at P˂0.05 compared to rats injected only with cisplatin. Moreover, it restored normal ovarian histological structure with a concurrent reduction in FSH, and LH levels, and increased AMH and ovarian hormone concentrations at P˂0.05 compared to cisplatin group. Also, RJ decreased the ovarian antioxidant/oxidative imbalance harmonized with significant suppression of inducible nitric oxide synthase and increase of quinone oxidoreductase 1 mRNA expression at P˂0.05 compared to cisplatin group.

CONCLUSION

We concluded that RJ could alleviate mitochondrial-induced ovarian apoptosis caused by cisplatin via increasing anti-apoptotic Bcl2, and diminishing pro-apoptotic Bax with a concomitant increase of Mfn2 mRNA and protein expressions.

Oral treatment with royal jelly improves memory and presents neuroprotective effects on icv-STZ rat model of sporadic Alzheimer's disease

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by progressive decline in cognitive function. Intracerebroventricular injection of streptozotocin (icv-STZ) has been used as an experimental model of Sporadic AD (SAD) in rodents and represents a promising tool for etiopathogenic analysis and evaluation of new therapeutic proposals for AD. The icv-STZ model shows many aspects of SAD abnormalities, resulting in decreased brain glucose and energy metabolism, cognitive impairment, oxidative stress, neuronal loss, and amyloid angiopathy. Royal jelly (RJ), a substance produced by worker honeybees of the Apis mellifera species, has been popularly used for more than 30 years in areas related to health eating and natural medicine. Researches indicate that RJ has a several pharmacological activities, including neuroprotective and improvement of cognitive function. The objective of this study was to investigate the effects of oral treatment with royal jelly during 2 weeks in Wistar rats submitted to icv-STZ on a working memory and neuroprotection, as evaluated by neurogenesis, neurodegeneration and oxidative stress. In this study, icv-STZ injection induced deleterious effects in the hippocampus, associated with cognitive impairments, and developed marked neurodegeneration, besides the reduction of neurogenesis and increased oxidative stress. On the other hand, RJ long-term oral administration induced beneficial effects in animals injured by icv-STZ injection, increasing retention time for working spatial memory, reducing neurodegeneration and oxidative stress level and increasing the proliferation of new neurons in the hippocampus. Thus, RJ promotes beneficial effects on cognitive functions and exhibits a neuroprotective action in the STZ experimental model of SAD.

Useful impacts of royal jelly on reproductive sides, fertility rate and sperm traits of animals

Royal jelly (RJ) is one of the furthermost valuable curative products mentioned by natural medicine scientists due to its promising medical and nutritional purposes. It possesses many impacts, including antioxidants, antimicrobial, antitumor, anti-inflammatory and immunomodulatory functions in human and animal that benefit their health and welfare, resulting in its widespread use in medical and commercial products and healthy food. Recently, favourable functions of RJ on male fertility have been reported in different animals. According to earlier literatures, the level of RJ supplementation in animal diet ranged from 100 to 200 mg/kg. Oral exposure to RJ has been reported to have oestrogenic influences in the adult female rats. Also, RJ may be influential in improvement of pregnancy and lambing rates of ewes. Oral administration of RJ at 100 mg/kg diet before sexual maturity enhanced sexual behaviour and semen quality of male rabbits. Moreover, RJ administration (up to 400 mg/kg diet once weekly) for male rabbits exposed to heat stress can counteract "summer infertility" and improve physiological responses. Furthermore, supplementation of freezing extender media with 0.1 or 3% RJ had a protective influence on cryopreserved and chilled spermatozoa of buffalo and ram respectively. However, the high dose of RJ oral administration (800 mg/kg) by pubescent male rats for 1 month had an undesirable effect on the reproductive system; however, the somewhat unfavourable influences were mitigated by the discontinuation of the administration. This review shows the chemical composition, favourable applications and health benefits of RJ and its effects on reproductive aspects, semen quality and in vitro fertilization outcomes which are advantageous for scientists, researchers, nutritionists, physiologists, embryologists, pharmacists, veterinarians, pharmaceutical industries and animal's breeders.

Royal jelly attenuates nonalcoholic fatty liver disease by inhibiting oxidative stress and regulating the expression of circadian genes in ovariectomized rats

Nonalcoholic fatty liver disease (NAFLD) has a high incidence in postmenopausal women and is accompanied by insulin resistance, obesity, and dyslipidemia. Royal jelly (RJ), a natural substance derived from hive, possesses numerous health-beneficial properties. Here, we evaluated the effects of RJ (150, 300, and 450 mg kg^-1  day^-1 , 8 weeks) on NAFLD in ovariectomized (OVX) rats. Based on the results, RJ ameliorated the degree of anxiety, improved serum lipid profile, and attenuated the hepatic steatosis and liver injury in OVX rats. Furthermore, the protective effects of RJ could be attributed to its antioxidant properties, which enhance the levels of hepatic antioxidant enzymes. The qRT-PCR results also suggest that RJ improves the disturbances of circadian genes by downregulating their expression, including that of Per1 and Per 2, in the liver of OVX rats. Altogether, our findings suggest that RJ may be a promising agent for the treatment of NAFLD. PRACTICAL APPLICATIONS: Postmenopausal women are at an increased risk of NAFLD. Currently, there are no licensed therapies for NAFLD. Although hormone replacement therapy (HRT) is reported to inhibit the development of NAFLD, it causes unexpected adverse effects. As HRT is controversial, the use of natural supplements to counteract the detrimental effects of menopause has recently attracted more attention. RJ is a natural product secreted from the hypopharyngeal and mandibular glands of worker bees. The present study illustrates the protective effect of the natural product, RJ, and its underlying mechanisms on NAFLD. This is the first study to assess the effect of RJ on NAFLD under estrogen deficiency. Such findings contribute to the further utilization of RJ, which might serve as a promising therapeutic option and natural food for the treatment of NAFLD.

Attenuation potentials of royal jelly against hydroxyurea-induced infertility through inhibiting oxidation and release of pro-inflammatory cytokines in male rats

Hydroxyurea (HDU), a class of antineoplastic drugs, has a powerful efficacy in the treatment of several types of malignancies. However, it has multiple adverse effects including reduced fertility, especially in males. Thus, 60 male albino rats were used to investigate the chemoprotective potentials of royal jelly on HDU-induced testicular damage. Animals were gastro-gavaged with HDU (225 or 450 mg kg^-1 bw day^-1) before royal jelly (100 mg kg^-1 bw day^-1) for 60 days. Blood samples and testicles were collected, and spermatozoon was obtained. In a dose-dependent manner, the sperm count, motility and liveability, and testosterone, GSH, and catalase concentrations were decreased in HDU groups, whereas MDA, FSH, LH, IL-6, and IFN-γ expression levels were increased. Germinal epithelium degeneration, germ cell sloughing, reduction in the number of luminal spermatozoa, interstitial congestion, and severe leukocyte infiltration besides no glandular secretion in most of the acini were identified. However, royal jelly intake in HDU-treated rats successfully improved sperm quality, hormonal and antioxidant status, and reproductive organ histoarchitecture. Thus, it could be concluded that royal jelly is endowed with antioxidative and anti-inflammatory activities and could be, therefore, used as an adjuvant remedy to improve HDU-induced male subfertility.

Royal jelly protects male rats from heat stress-induced reproductive failure

Royal jelly (RJ) as an antioxidant has been shown to have attenuated oxidative stress damages in reproductive organs. The objective was carried out the effects of RJ on sperm characteristics, sperm malondialdehyde (MDA) concentration and in vitro fertilisation (IVF) outcome in heat stress (HS) exposed male rats. Forty-eight male rats were randomly divided into eight groups; group 1 received normal saline, group 2 received RJ (100 mg kg^-1  day^-1 ; PO), groups 3, 4 and 5 were heat-stressed (43, 39 and 37°C for 20 min per day respectively) and groups 6, 7 and 8 were heat-stressed along with RJ (43, 39 and 37°C for 20 min per day, respectively, plus RJ at a dose of 100 mg kg^-1  day^-1 ; PO). The HS was induced through immersion of experimental rat scrotums in a water bath. After 48 days, the HS induced remarkable diminish in sperm motility, viability and fertilising potential along with reduced blastulation rate and enhanced sperm chromatin abnormality, MDA levels and DNA damage. Nevertheless, RJ co-administration improved sperm characteristics and early embryo development as well as sperm lipid peroxidation level. Our data suggest that RJ can effectively ameliorate the experimental HS-induced infertility in rats through MDA concentration restoration and sperm characteristics and pre-implantation embryo development improvement.

Royal Jelly Abrogates Cadmium-Induced Oxidative Challenge in Mouse Testes: Involvement of the Nrf2 Pathway

The current study examined the efficacy of royal jelly (RJ) against cadmium chloride (CdCl₂)-induced testicular dysfunction. A total of 28 Swiss male mice were allocated into four groups (n = 7), and are listed as follows: (1) the control group, who was intraperitoneally injected with physiological saline (0.9% NaCl) for 7 days; (2) the RJ group, who was orally supplemented with RJ (85 mg/kg daily equivalent to 250 mg crude RJ) for 7 days; (3) the CdCl₂ group, who was intraperitoneally injected with 6.5 mg/kg for 7 days; and (4) the fourth group, who was supplemented with RJ 1 h before CdCl₂ injection for 7 days. Cd-intoxicated mice exhibited a decrease in serum testosterone, luteinizing hormone (LH), and follicle stimulating hormone (FSH) levels. A disturbance in the redox status in the testicular tissue was recorded, as presented by the increase in lipid peroxidation and nitrate/nitrite levels and glutathione (GSH) depletion. Moreover, the activities of glutathione peroxidase (GPx), glutathione reductase (GR), superoxide dismutase (SOD), catalase (CAT), and nuclear factor (erythroid-derived 2)-like-2 factor (Nrf2) and their gene expression were inhibited. In addition, interleukin-1ß (IL-1β) and tumor necrosis factor-α (TNF-α) levels were elevated. Furthermore, Cd triggered an apoptotic cascade via upregulation of caspase-3 and Bax and downregulation of Bcl-2. Histopathological examination showed degenerative changes in spermatogenic cells, detachment of the spermatogenic epithelium from the basement membrane, and vacuolated seminiferous tubules. Decreased cell proliferation was reflected by a decrease in proliferating cell nuclear antigen (PCNA) expression. Interestingly, RJ supplementation markedly minimized the biochemical and molecular histopathological changes in testes tissue in response to Cd exposure. The beneficial effects of RJ could be attributed to its antioxidative properties.

Royal jelly mitigates cadmium-induced neuronal damage in mouse cortex

This study aimed to evaluate the potential neuroprotective effect of royal jelly (RJ) against Cd-induced neuronal damage. Twenty-eight adult mice were placed equally into four groups. The control group received intraperitoneal (IP) injections of normal saline; the cadmium chloride (CdCl₂) group was IP-injected 6.5 mg/kg (mg per kg of bodyweight) CdCl₂; the RJ group was gavaged 85 mg/kg RJ; and the RJ + CdCl₂ group was orally administered 85 mg/kg RJ 2 h before receiving IP-injections of 6.5 mg/kg CdCl₂. All groups were treated for seven consecutive days and the mice were decapitated 24 h after the final dose. Cd accumulation was recorded in the cortical homogenates, accompanied by elevated levels of lipid peroxidation, nitric oxide, tumor necrosis factor-α, interleukin-1β, and the pro-apoptotic mRNA Bax and caspase-3. Meanwhile, significantly decreased levels of detoxifying antioxidant enzymes including GSH-Px, GSH-R, SOD, and CAT, anti-apoptotic mRNA Bcl-2, and monoamines such as norepinephrine, dopamine, and serotonin were also observed, along with reduced gene expression of Nrf2-dependent antioxidants. Interestingly, in mice pretreated with RJ, the assessed parameters remained near normal levels. Our data provide evidence that RJ treatment has the potential to protect cortical neurons in Cd-intoxicated mice via its antioxidant, anti-inflammatory, anti-apoptotic, and neuromodulatory activity.

Royal jelly protects male mice against nicotine-induced reproductive failure

This study evaluated the possible protective effect of royal jelly (RJ) on sperm parameters and sperm malondialdehyde (MDA) concentration and in vitro fertilizing potential in nicotine (NIC) exposed male mice. Thrtiy-six male BALB/c mice were randomly divided into six groups (n = 6). Group 1 received normal saline, group 2 received 100 mg kg-1 per day RJ, groups 3 and 4 received NIC at doses of 0.50 and 1.00 mg kg-1 per day, respectively and groups 5 and 6 received NIC at doses of 0.50 and 1.00 mg kg-1 per day, respectively plus RJ. Caudal epididymal sperm characteristics, lipid peroxidation and in vitro fertilizing capacity and embryo development were evaluated after 35 days. The NIC treatment caused a significant decrease in sperm motility and viability and fertilization rate along with poor blastocyst formation and increased sperm DNA damage and MDA levels. Moreover, the incidences of chromatin abnormality in spermatozoa were significantly higher in NIC-exposed mice than those of control. Nevertheless, RJ treatment improved sperm parameters and in vitro fertilization outcome as well as sperm lipid peroxidation level. Data from the current study suggest that RJ has a potential repro-protective action against NIC-induced sperm abnormalities and embryotoxicity in mice.

Peptide identification in alcalase hydrolysated pollen and comparison of its bioactivity with royal jelly

Peptides with a similar antioxidant and ACE-inhibitory activity of royal jelly (RJ) generated from Alcalase hydrolysated pollen (AHP) were predicted by Response Surface Methodology (RSM). The model equations were proposed according to the effects of time and enzyme concentration on the antioxidant and ACE-inhibitory activity. The optimum values for Alcalase concentration and hydrolysis time were 1.5% and 4 h, respectively. Later, AHP was prepared and deproteinised to be further analysed using size-exclusion chromatography (SEC). After SEC separation, fractions with the highest activity of ACE-inhibitory, DPPH radical scavenging and ferric-reducing power were purified by RP-HPLC. The highest ACE-inhibitory and DPPH scavenging activity of fractions was found 100% and 66.61%, respectively. The most active fractions were analysed by nano-liquid chromatography and mass spectrometry in tandem (nLC-MS/MS) and a total of 195 peptide sequences were identified. The origins of all peptides were herbal proteins and certain coincidences with previously described bioactive sequences were discussed.

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.

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.

Possible protective effect of royal jelly against cyclophosphamide induced prostatic damage in male albino rats; a biochemical, histological and immuno-histo-chemical study

Almost all the chemotherapy treat many cancer types effectively, but it leads to severe side effects. Chemotherapy like cyclophosphamide (CP) not works only on the active cells, such as cancer cells, but also acts on the healthy cells. Royal jelly (RJ) was reported to have a lot of therapeutic effects besides being an anti-oxidant and anti-cancer agent. The purpose of this study was to assess the possible protective role of RJ in ameliorating the toxic effects of CP overdose in the rat prostatic tissue. The rats were separated into 4 groups; control group, RJ group, CP group and RJ with CP group. Prostatic specimens were processed for biochemical, histological and immune-histo-chemical studies. The mean area fractions of eNOS and Bax expression were measured in all groups, and statistical analysis was carried out. The results showed that in CP treated group, there were marked biological changes in the form of significant increase in prostatic malondialdehyde (MDA) and C - reactive protein (CRP). Additionally there was a significant decrease in glutathione peroxidase (GPx) in prostatic tissue if compared with the control group. Furthermore, the histological changes showed marked acinar and stromal prostatic degeneration. Most prostatic acini showed less PAS reaction and more (eNOS and Bax) expression if compared with the control group. Concomitant administration of RJ with CP revealed a noticeable amelioration of these biochemical and histological changes. In conclusion, RJ provided biochemical and histo-pathological improvement in CP induced prostatic tissue toxicity. These findings revealed that this improvement was associated with a decrease in the tissue oxidative damage and apoptosis.

Improvement in Serum Biochemical Alterations and Oxidative Stress of Liver and Pancreas following Use of Royal Jelly in Streptozotocin-Induced Diabetic Rats

OBJECTIVE

This study aimed to evaluate the effects of royal jelly (RJ) on serum biochemical alterations and oxidative stress status in liver and pancreas of streptozotocin (STZ)- induced diabetic rats.

MATERIALS AND METHODS

In this experimental study, thirty two male Wistar rats were divided into the following four groups (n=8/group): i. Control (C), ii. Diabetic (D), iii. Royal jelly (R), and iv. Royal jelly-treated diabetic (D/R) groups. Diabetes was induced by single intraperitoneal (IP) injection of STZ (60 mg/kg). The RJ [100 mg/kg body weight (BW)] was administered orally for 42 days. Blood samples were used to determine serum levels of insulin, high density lipoprotein cholesterol (HDL-c), total protein (TP), albumin, alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), and fasting blood glucose (FBG). Also, the antioxidant status was evaluated by determining the levels of malondialdehyde (MDA), catalase (CAT) and ferric reducing antioxidant power (FRAP) in liver and pancreas. Data were analyzed by one-way analysis of variance (ANOVA) with P<0.05 as the significant level.

RESULTS

STZ-induced diabetic rats showed a significant elevation in the serum levels of AST, ALT, ALP and FBG, whereas there was a significant decrease in serum levels of insulin, albumin, HDL-c and TP (P<0.05). Treatment of the diabetic rats with RJ restored the changes of the above parameters to their normal levels (P<0.05). In addition, RJ significantly improved reduced levels of FRAP and CAT as well as high MDA level in liver and pancreas (P<0.05).

CONCLUSION

RJ improves oxidative damage induced by STZ in the liver and pancreas of rats; therefore, it can be considered as an effective and alternative treatment for diabetes.

Long-term treatment with royal jelly improves bleomycin-induced pulmonary fibrosis in rats

This study investigated the anti-fibrotic potential of royal jelly (RJ) powder against bleomycin-induced pulmonary fibrosis in rats. The rats were given RJ orally (25, 50, and 100 mg/kg per day) for 7 consecutive days before the administration of single intratracheal instillation of bleomycin (BLM) at 7.5 IU/kg. RJ doses were continued for 21 days after BLM exposure. Fibrotic changes in the lungs were studied by cell count and analysis of cytokine levels in the bronchoalveolar lavage fluid (BALF), histopathological examination, and assaying oxidative stress biomarkers in lung tissue. The results showed that BLM administration significantly increased the fibrotic changes, collagen content, and levels of malondialdehyde and decreased total thiol and glutathione peroxidase antioxidant contents in the rats' lung tissue. An increase in the level of cell counts and pro-inflammatory and pro-fibrotic cytokines such as TNF-α and TGF-β in BALF was observed. Also, it significantly decreased IFN-γ, an anti-fibrotic cytokine, in BALF. However, RJ (50 and 100 mg/kg) reversed all of these biochemical indices as well as histopathological alterations induced by BLM. The present study demonstrates that RJ, by its antioxidant and anti-inflammatory properties, attenuates oxidative damage and fibrosis induced by BLM.

Effect of Royal Jelly Intake on Serum Glucose, Apolipoprotein A-I (ApoA-I), Apolipoprotein B (ApoB) and ApoB/ApoA-I Ratios in Patients with Type 2 Diabetes: A Randomized, Double-Blind Clinical Trial Study

OBJECTIVES

Type 2 diabetes is the most common metabolic disorder worldwide. Evidence supports a role for royal jelly (RJ) in reduction of serum glucose and lipids in animals and healthy subjects. The purpose of this study was to determine the effect of RJ intake on serum glucose, apolipoprotein A-I (ApoA-I), apolipoprotein B (ApoB) and ApoB/ApoA-I ratios in patients with type 2 diabetes.

METHODS

Fifty patients with type 2 diabetes participated in a double-blind, placebo-controlled study. The participants were randomly divided into RJ and placebo groups and were given doses of 1000 mg royal jelly or placebo 3 times a day for 8 weeks, respectively. Weight, height, fasting blood glucose, ApoA-I and ApoB were measured at baseline and endpoint.

RESULTS

There were no significant differences in baseline characteristics and dietary intakes between groups. The mean difference in glucose concentrations decreased in the RJ group (-9.4 mg/dL vs. 4 mg/dL; p=0.011). The mean difference in ApoA-I concentrations increased in the RJ group (34.4 mg/dL vs. -1.08 mg/dL; p=0.013). There was a significant decrease in mean difference of ApoB/ApoA-I in the RJ group compared with the placebo group (0.008 vs. 0.13; p<0.044), respectively.

CONCLUSIONS

These data suggest that RJ intake may have desirable effects on serum glucose, Apo-A-I concentrations and ApoB/ApoA-I ratios in people with type 2 diabetes.

Effect of Royal Jelly on new bone formation in rapid maxillary expansion in rats

Background

The aim of this study was to evaluate the effects of long and short term systemic usage of royal jelly on bone formation in the expanded maxillary suture in a rat model.

Material and Methods

Twenty eight Wistar albino rats were randomly divided into 4 equal groups: Control (C); Only Expansion (OE), Royal Jelly (RJ) group, Royal Jelly was given to rats by oral gavage only during the expansion and retention period; Royal Jelly plus Nursery (RJN) group, Royal Jelly was given to rats by oral gavage during their nursery phase of 40 days and during the retention period. After the 5 day expansion period was completed, the rats underwent 12 days of mechanical retention. All rats were sacrificed in same time. Histological examination was performed to determine the number of osteoclasts, number of osteoblasts, number of capillaries, inflammatory cell infiltration, and new bone formation.

Results

New bone formation, number of osteoclasts, number of osteoblasts, and the number of capillaries in the expanded maxillary sutures were higher in the RJ and RJN groups than in the other groups. Statistical analysis also demonstrated that new bone formation and the number of osteoblasts was also highest in the RJN group.

Conclusions

The systemic administration of Royal Jelly in conjunction with rapid maxillary expansion may increase the quality of regenerated bone.

Key words:Bone formation, rapid maxillary expansion, Royal jelly.

Study on the effect of royal jelly on reproductive parameters in streptozotocin-induced diabetic rats

Background

Diabetes mellitus has a variety of structural and functional effects on the male reproductive system. Diabetes results in reduced sperm parameters and libido. The present study aims to investigate the effects of royal jelly (RJ) on reproductive parameters of testosterone and malondialdehyde (MDA) production in diabetic rats.

Materials and Methods

This experimental study was conducted on adult male Wistar rats. The animals were divided into four groups (n=8 per group): control, RJ, diabetic and diabetic treated with RJ. Diabetes was induced by intraperitoneal injection of 60 mg/kg body weight (BW) of streptozotocin (STZ). RJ, at a dose of 100 mg/kg BW was given by gavage. The duration of treatment was six weeks. After the treatment period the rats were sacrificed. The testes were weighed and changes in sperm count, motility, viability, deformity, DNA integrity and chromatin quality were analyzed. Serum testosterone and MDA concentrations of testicular tissue were determined. Data were analyzed by oneway ANOVA with p<0.05 as the significant level.

Results

STZ-induced diabetes decreased numerous reproductive parameters in rats. Testicular weight, sperm count, motility, viability and serum testosterone levels increased in the diabetic group treated with RJ. There was a significant decrease observed in sperm deformity, DNA integrity, chromatin quality, and tissue MDA levels in diabetic rats treated with RJ compared to the diabetic group (p<0.05).

Conclusion

RJ improved reproductive parameters such as testicular weight, sperm count, viability, motility, deformity, DNA integrity, chromatin quality, serum testosterone and testicular tissue MDA levels in diabetic rats.

Antioxidant activities and contents of flavonoids and phenolic acids of Talinum triangulare extracts and their immunomodulatory effects

In this study, leaves and stems of Talinum triangulare were sequentially extracted with phosphate buffer solution to obtain PTL and PTS (phosphate buffered extracts of T. triangulare leaves and stems), with 75% ethanol to obtained ETL and ETS (ethanol extracts of T. triangulare leaves and stems), or with 90°C boiling water to obtain WTL and WTS (water extracts of T. triangulare leaves and stems). We investigated the antioxidant activities of various T. triangulare extracts, analyzed the extracts’ stimulations on human mononuclear cell (MNC) growth and secretion of cytokines (interleukin-1 beta, interferon-γ, and tumor necrosis factor-α) and nitric oxide, and then assayed their subsequent inhibitions on human leukemic U937 cell growth. Results indicated that extracts of T. triangulare showed significant antioxidant activities. Among these extracts, WTS showed the highest stimulatory effect on human MNC growth. The secretion levels of interleukin-1 beta, interferon-γ, and tumor necrosis factor-α in the conditioned medium, wherein human MNC was treated with 500 μg/mL WTS for 72 hours, were 1275, 859, and 2222 pg/mL, respectively. All conditioned media obtained from human MNCs cultured with various T. triangulare extracts showed significant inhibition against U937 cell growth of over 40%. These results suggest that T. triangulare extracts may be used in health foods for their immunomodulatory potential.

Effects of royal jelly supplementation on glycemic control and oxidative stress factors in type 2 diabetic female: a randomized clinical trial

OBJECTIVE

It has been proposed that royal jelly has antioxidant properties and may improve oxidative stress and glycemic control. Therefore, we investigated the effects of royal jelly supplementation in diabetic females.

METHODS

In this pilot, parallel design randomized clinical trial, 50 female volunteers with type 2 diabetes were randomly allocated to the supplemented (25, cases) and placebo (25, cases) groups, based on random block procedure produced by Random Allocation Software, given a daily dose of 1,000 mg royal jelly soft gel or placebo, respectively, for 8 weeks. Before and after intervention, glycemic control indices, antioxidant and oxidative stress factors were measured.

RESULTS

After royal jelly supplementation, the mean fasting blood glucose decreased remarkably (163.05±42.51 mg/dL vs. 149.68±42.7 mg/dL). Royal jelly supplementation resulted in significant reduction in the mean serum glycosylated hemoglobin levels (8.67%±2.24% vs. 7.05%±1.45%, P=0.001) and significant elevation in the mean insulin concentration (70.28±29.16 pmol/L vs. 86.46±27.50 pmol/L, P=0.01). Supplementation significantly increased erythrocyte superoxidase dismutase and glutathione peroxidase activities and decreased malondialdehyde levels (P<0.05). At the end of study, the mean total antioxidant capacity elevated insignificantly in both groups.

CONCLUSIONS

On the basis of our findings, it seems that royal jelly supplementation may be beneficial in controlling diabetes outcomes. Further studies with larger sample size are warranted.

Royal jelly: can it reduce physiological strain of growing rabbits under Egyptian summer conditions?

Exposure of growing rabbits to heat stress during summer adversely affects their performance leading to major production losses. A total number of 48 rabbits, unsexed V-line weaned rabbits, were randomly divided into four experimental groups, temperature ranged from high at 32°C to low at 23°C. Animals of the 2nd, 3rd and 4th group were individually orally given 200, 400 or 800 mg royal jelly (RJ)/kg BW once a week, respectively, to evaluate RJ ability to reduce physiological strain resulted from heat stress. Weekly BW gain increased by 10.4, 11.8 and 10.8%, and feed conversion ratio was significantly improved by 20, 24 and 18% with RJ treatments. Serum total protein, albumin and globulin increased, whereas serum total lipids, cholesterol and triglycerides decreased with RJ treatments. Creatinine was reduced by 21, 30 and 18% and uric acid by 14, 25 and 18% compared with the heat stressed control with the three doses of RJ. Glucose level increased significantly to reach 116, 125, and 120% of heat stressed control. Calcium, phosphorus and alkaline phosphatase increased significantly with RJ treatments indicating the occurrence of active bone deposition. Thyroid hormone levels increased significantly to reach 108, 111, and 112% of heat stressed control rabbits with the three doses of RJ, counteracting the hypothyroid state resulted from heat stress. It can be concluded that RJ administration to heat stressed growing rabbits can reduce physiological strain resulted from heat stress.

Effect of Royal Jelly on spatial learning and memory in rat model of streptozotocin-induced sporadic Alzheimer's disease

Background:

It has been recently demonstrated that Royal jelly (RJ) has a beneficial role on neural functions. Alzheimer's disease (AD) is associated with impairments of learning and memory. Therefore, the present study was designed to examine the effect of RJ on spatial learning and memory in rats after intracerebroventricular injection of streptozotocin (icv-STZ).

Materials and Methods:

Rats were infused bilaterally with an icv injection of STZ, while sham rats received vehicle only. The rats were feed with RJ-contained food (3% w/w) (lyophilized RJ mixed with powdered regular food) or regular food for 10 days. Then spatial learning and memory was tested in the rats by Morris water maze test.

Results:

Results showed that in icv-STZ group latency and path length were increased as compared to sham group, also icv-STZ rats less remembered the target quadrant that previously the platform was located; however, these were protected significantly in STZ group that received RJ-containing food.

Conclusions:

Our findings support the potential neuroprotective role of RJ and its helpful effects in AD.

Lifespan-extending effects of royal jelly and its related substances on the nematode Caenorhabditis elegans

Background

One of the most important challenges in the study of aging is to discover compounds with longevity-promoting activities and to unravel their underlying mechanisms. Royal jelly (RJ) has been reported to possess diverse beneficial properties. Furthermore, protease-treated RJ (pRJ) has additional pharmacological activities. Exactly how RJ and pRJ exert these effects and which of their components are responsible for these effects are largely unknown. The evolutionarily conserved mechanisms that control longevity have been indicated. The purpose of the present study was to determine whether RJ and its related substances exert a lifespan-extending function in the nematode Caenorhabditis elegans and to gain insights into the active agents in RJ and their mechanism of action.

Principal Findings

We found that both RJ and pRJ extended the lifespan of C. elegans. The lifespan-extending activity of pRJ was enhanced by Octadecyl-silica column chromatography (pRJ-Fraction 5). pRJ-Fr.5 increased the animals' lifespan in part by acting through the FOXO transcription factor DAF-16, the activation of which is known to promote longevity in C. elegans by reducing insulin/IGF-1 signaling (IIS). pRJ-Fr.5 reduced the expression of ins-9, one of the insulin-like peptide genes. Moreover, pRJ-Fr.5 and reduced IIS shared some common features in terms of their effects on gene expression, such as the up-regulation of dod-3 and the down-regulation of dod-19, dao-4 and fkb-4. 10-Hydroxy-2-decenoic acid (10-HDA), which was present at high concentrations in pRJ-Fr.5, increased lifespan independently of DAF-16 activity.

Conclusions/Significance

These results demonstrate that RJ and its related substances extend lifespan in C. elegans, suggesting that RJ may contain longevity-promoting factors. Further analysis and characterization of the lifespan-extending agents in RJ and pRJ may broaden our understanding of the gene network involved in longevity regulation in diverse species and may lead to the development of nutraceutical interventions in the aging process.

Royal jelly counteracts bucks' "summer infertility"

Exposure of male rabbits to heat stress during summer adversely affects their fertility leading to major production losses. A total number of 24 male rabbits were randomly divided into four experimental groups exposed to temperatures ranging from a high of 32 degrees C to a low of 23 degrees C. Animals of the 2nd, 3rd and 4th group were individually orally given 200, 400, or 800 mg royal jelly (RJ)/kg body weight once a week to evaluate the ability of RJ feeding to counteract "summer infertility" in bucks and enhance their physiological status. Royal jelly treatments significantly boosted testosterone level to 133, 143 and 124% of basal, increased ejaculated volume by 36, 31 and 18%, increased seminal plasma fructose to 122, 124, and 111%, improved sperm motility by 15, 18 and 5%, increase sperm total output by 65, 63 and 35%, reduced abnormal sperm by 24, 24 and 15% and dead sperm by 27, 25 and 17% compared to the heat stressed control animals. Serum total protein, albumin and globulin increased while serum total lipids, cholesterol and triglycerides decreased with RJ treatments. Creatinine was reduced by 5, 13 and 8% and uric acid by 4, 7 and 4%, respectively for the three doses of RJ compared to control. Alkaline phosphatase has significantly increased to reach 114, 118, and 108% of heat stressed level with the three doses of RJ, indicating the occurrence of active bone deposition. Glucose level increased significantly to reach 105, 112, and 116% of heat stressed control and both calcium and phosphorus increased significantly with RJ treatments. It was concluded that royal jelly administration to heat stressed male rabbits can counteract their "summer infertility" and improve their physiological status.

Royal jelly ameliorates insulin resistance in fructose-drinking rats

Royal jelly (RJ) is known to contain excellent nutrition and a variety of biological activities. The present study was designed to investigate the effects of RJ on insulin resistance (hyperinsulinemia) in fructose-drinking rats (FDR; insulin resistance animal model). Male Wistar rats (6 weeks old) received 15% fructose solution in drinking water for 8 weeks. FDR showed significant increases in plasma levels of insulin and triglyceride, Homeostasis Model Assessment ratio (HOMA-R, an index of insulin resistance), and systolic blood pressure, but not blood glucose levels, when compared with control rats. RJ (100, 300 mg/kg, p.o.) treatment for 8 weeks significantly decreased the plasma levels of insulin and triglyceride, HOMA-R, without affecting blood glucose or total cholesterol levels and tended to lower systolic blood pressure. In isolated and perfused mesenteric vascular beds of FDR, RJ treatment resulted in a significant reduction in sympathetic nerve-mediated vasoconstrictor response to periarterial nerve stimulation (PNS) and tended to increase the calcitonin gene-related peptide (CGRP) nerve-mediated vasodilator response to PNS, compared with those in untreated FDR. However, RJ treatment did not significantly affect norepinephrine-induced vasoconstriction or CGRP-induced vasodilation. These results suggest that RJ could be an effective functional food to prevent insulin resistance associated with the development of hypertension.