Protective effect of bee pollen in acute kidney injury, proteinuria, and crystalluria induced by ethylene glycol ingestion in rats

Oxidative stress plays a role in hyperoxaluria-induced kidney injury and crystallization. Bee pollen is a hive product with a high content of antioxidants. The antioxidant content and protective effect of bee pollen extract (BPE) against ethylene glycol (EG) induced crystalluria, and acute kidney injury (AKI) were investigated. The effect of BPE on the EG-induced liver injury and proteinuria was also examined. Ten groups of male Wister rats were treated daily with vehicle, cystone, BPE (100, 250, and 500 mg/kg b.wt.), and group 6–9 treated with EG, EG + BPE (100, 250, and 500 mg/kg b.wt.) and group 10 EG + cystone. The dose of EG was 0.75% v/v, and the dose of cystone was 500 mg/kg b.wt. On day 30, blood and urine samples were collected for analysis. Kidneys were removed for histopathological study. The antioxidant activity of BPE was assessed, and its total phenols and flavonoids were determined. EG significantly increased urine parameters (pH, volume, calcium, phosphorus, uric acid, and protein), blood urea, creatinine, and liver enzymes (P < 0.05). EG decreased creatinine clearance and urine magnesium and caused crystalluria. Treatment with BPE or cystone mitigates EG's effect; BPE was more potent than cystone (P < 0.05). BPE increases urine volume, sodium, and magnesium compared to the control and EG treated groups. BPE reduces proteinuria and prevents AKI, crystalluria, liver injury, and histopathological changes in the kidney tissue caused by EG. BPE might have a protective effect against EG-induced AKI, crystalluria, proteinuria, and stone deposition, most likely by its antioxidant content and activity.

Arbutus Unedo Honey and Propolis Ameliorate Acute Kidney Injury, Acute Liver Injury, and Proteinuria via Hypoglycemic and Antioxidant Activity in Streptozotocin-Treated Rats

BACKGROUND/AIMS

Honey and propolis have biological and therapeutic effects in various pathological and clinical conditions such as hyperglycemia and diabetes. However, the combined use of honey and propolis has not been reported. The study evaluated the protective effect of Arbutus unedo honey, propolis and their combination in streptozotocin (STR)-induced hyperglycemia, acute kidney injury (AKI), liver injury, dyslipidemia, and proteinuria in male Wistar rats.

METHODS

The study identified physicochemical characteristics, mineral and antioxidant content, and antioxidant activity in honey and propolis. Rats were assigned to five groups, with five rats in each group; control, STR-treated, STR-treated + honey (1g/kg/day), STR-treated + propolis (100 mg/day), and STR-treated + honey and propolis. On day 15, blood glucose, insulin, HBA1c, kidney function tests, liver enzymes, lipid profile, hemoglobin, and urine protein, creatinine, glucose, and electrolytes were analyzed. Liver, pancreas, and kidney tissues were studied histologically. The mineral component in honey and propolis was determined by atomic absorption spectrometry. Honey analysis was performed by HPLC. Chemical characterization of propolis was performed by LC/DAD/ESI-MSⁿ . Measurement of blood and urine parameters was carried out with an automated analyzer (Architect c8000) and XT-1800i Automated Hematology Analyzer. Insulin concentration was determined by Elisa and insulin resistance was estimated by using HOMA-IR.

RESULTS

Honey and propolis contain a high quantity of antioxidants and exhibit in vitro antioxidant activity. In STR-treated rats, blood glucose, HBA1c, creatinine, blood urea, liver enzymes, and urine protein significantly increased compared to the control group (P<0.05), while insulin, hemoglobin, and body weight significantly decreased. Histological changes were evident in the pancreas, kidney, and liver tissues. These results indicated AKI, liver injury, and pancreatic injury, which was evident with reducing the number of the island of Langerhans and marked hyperglycemia. The use of honey and propolis significantly (P<0.05) attenuated liver and kidney injury, and proteinuria, and improved level of hemoglobin, HBA1c, and insulin toward the normal range. The combination of honey and propolis was more effective than honey or propolis individually (P<0.05).

CONCLUSION

the combination of propolis and honey can prevent STR-induced AKI, liver injury, proteinuria, dyslipidemia, anemia, hyperglycemia, and body weight loss, most likely by their hypoglycemic and antioxidant activities.

Physicochemical characterization and in vitro evaluation of the antioxidant and anticandidal activities of Moroccan propolis

Background and Aim:

Human mycotic infections are one of the major health problems worldwide. Prolonged use of antimycotic drugs has contributed to the development of resistance in pathogenic fungi. This study was conducted to examine antioxidant and anticandidal activities of Moroccan propolis.

Materials and Methods:

Two ethanolic extracts of Moroccan propolis from the Fez-Meknes region were evaluated regarding the following physicochemical parameters: Yield, pH, total carbohydrates, total proteins, total lipids, minerals, total phenolic content, total flavonoid content, and antioxidant activity using ferric reducing antioxidant power (FRAP) and 2,2’-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays. In addition, we assessed the in vitro anticandidal activity against vulvovaginal candidiasis strains, that is, Candida albicans, Candida glabrata, Candida parapsilosis, and Candida krusei, using the broth micromethod according to the CLSI/M27-A3 reference guidelines.

Results:

The propolis samples exhibited a mean yield of 16%, with an acidic pH ranging from 4.8 to 5.9; the sample from the Oued Amlil area (OAPEE) contained high levels of resin, balsam, moisture, total carbohydrates, and total lipids: 59.8%, 0.71%, 2%, 1.01 gGlcEq/g, and 120 mg/g, respectively. Moreover, the sample from the Sefrou area (SFPEE) was richer in total proteins and minerals, with values of 2.5 g/100 g and 1.84%, respectively. The total polyphenol and flavonoid content in the propolis extracts were 117.38 and 194.68 mg of gallic acid equivalent/g, and 17.45–27.79 mg of quercetin equivalent/g, respectively. Regarding the antioxidant activity, the most effective propolis extract was the sample from the Sefrou area, at 72.5 μg/mL and 118.78 μmoL Fe²⁺/g for ABTS-half-maximal inhibitory concentration and FRAP-half maximal effective concentration, respectively. The analysis of phenolic compounds using high-performance liquid chromatography with a diode-array detector revealed the presence of 13 polyphenols. The main compound in the OAPEE sample was epicatechin (310 mg/g), whereas in the SFPEE sample was apigenin (410 mg/g). Regarding the antifungal activity against Candida species, the minimum inhibitory concentration and minimum fungicidal concentration of the Moroccan propolis ethanolic extracts ranged between 31.2 and 62.5 μg/mL and 62.5 and 125 μg/mL, respectively, comparable with fluconazole (as a reference antimycotic).

Conclusion:

This study suggests that Moroccan propolis (31.2 and 125 μg/mL) may be an important source of bioactive molecules with anticandidal activity. Propolis may be a promising naturally-occurring candidate for the development of antimycotic drugs.

Moroccan Bee Bread Improves Biochemical and Histological Changes of the Brain, Liver, and Kidneys Induced by Titanium Dioxide Nanoparticles

Titanium dioxide nanoparticles (TiO2) were used in various fields such as food industry, cosmetics, medicine, and agriculture. Despite the many advantages of nanotechnology, the adverse effects of nanoparticles are inevitable. The present study was conducted to evaluate the protective effect of bee bread on titanium dioxide (TiO2) nanoparticle toxicity. Male rats were randomly divided into four groups: Group 1 received daily by gavage (10 mL/kg bw) of distilled water, Group 2 received bee bread ethanolic extract (100 mg/kg bw), Group 3 received TiO2 (100 mg/kg bw) and distilled water (10 mL/kg bw), and Group 4 received TiO2 (100 mg/kg bw) and bee bread ethanolic extract (100 mg/kg bw). All treatments were given daily by gavage during 30 days. At the end of the experiment period, blood samples were collected to analyze fasting blood glucose, lipid profile (TC, TG, LDL-C, HDL-C, and VLDL-C), liver enzymes (AST, ALT, and LDH), total protein, urea, albumin, creatinine, sodium, potassium, and chloride ions. In addition, histological examinations of the kidneys, liver, and brain were investigated. The results showed that the subacute administration of TiO2 alone (100 mg/kg bw) had induced hyperglycemia (309 ± 5 mg/dL) and elevation of hepatic enzyme levels, accompanied by a change in both lipid profile and renal biomarkers as well as induced congestion and dilatation in the hepatic central vein and congestion in kidney and brain tissues. However, the cotreatment with bee bread extract restored these biochemical parameters and attenuated the deleterious effects of titanium nanoparticles on brain, liver, and kidney functions which could be due to its rich content on functional molecules. The findings of this paper could make an important contribution to the field of using bee bread as a detoxifying agent against titanium dioxide nanoparticles and other xenobiotics.

Chemical composition and antioxidant content of Thymus vulgaris honey and Origanum vulgare essential oil; their effect on carbon tetrachloride-induced toxicity

Aim

The study investigated the chemical composition, antioxidant content, and antioxidant activity of Thymus vulgaris honey (TVH) and Origanum vulgare essential oil (OVEO) and their mixture effect on carbon tetrachloride (CCl₄)-induced toxicity.

Materials and Methods

The study conducted physicochemical characterization and chemical analysis of TVH and OVEO with the use of gas chromatography-mass spectrometry and high-performance liquid chromatograph (HPLC). The antioxidant activity of TVH and OVEO was done with the use of 1,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity. The study used nine groups of rats to investigate the effect of TVH, OVEO, and a mixture of TVH and OVEO (HEM) on CCl₄-induced toxicity. Intraperitoneal injection of CCl₄ (1 mL/100 g) was used to induce toxicity. The doses of TVH and OVEO were 1 mg/kg.b.wt, and 50 mg/kg.b.wt, respectively. HEM contains TVH (1 mg/kg.b.wt) and OVEO (50 mg/kg.b.wt).

Results

TVH has a high content of phenols, flavonoids, and flavanols. HPLC analysis showed that TVH contains, for the 1^st time, epicatechin gallate, and at a high concentration. OVEO includes a high percentage of carvacrol and thymol. With the use of DPPH, OVEO was more potent than TVH. CCl₄ caused significant liver and kidney damage and lipid disorders, which were alleviated by HVT, OVEO, and HEM. HVT was more potent than OVEO (p<0.05), and HEM was more potent than HVT and OVEO (p<0.05).

Conclusion

The study identified high content of epicatechin gallate for the 1^st time in TVH, and OVEO contains a high percentage of thymol and carvacrol. Epicatechin gallate might be useful as a marker for TVH. Mixing OVEO and TVH significantly potentiated their protection against CCl₄-induced liver and kidney toxicity.

Effect of antioxidant-rich propolis and bee pollen extracts against D-glucose induced type 2 diabetes in rats

The present study was designed to investigate the preventive effect of propolis, bee pollen and their combination on Type 2 diabetes induced by D-glucose in rats. The study was carried out by feeding daily two concentrations (100 and 200 mg/Kg BW) of propolis or bee pollen (or their combination to normal (non-diabetic) and diabetic rats for a period of 16 weeks. In vivo biochemical changes associated to diabetes are induced by drinking a solution containing 10% of D-glucose (diabetic rats). The in vitro antioxidant activity was also evaluated and the chemical composition of propolis and bee pollen extracts was determined by UHPLC-DAD. Phytochemical composition of propolis and bee pollen revealed the presence of several natural antioxidants, such as hydroxycinnamic acids, hydroxybenzoic acids, flavonoids, flavan-3-ols and stilbens. The major antioxidant compound present in propolis was Naringin (290.19 ± 0.2 mg/Kg) and in bee pollen was apigenin (162.85 ± 17.7 mg/Kg). These results have been related with a high antioxidant activity, more intense in propolis extract. In rats, the administration of D-glucose had induced hyperglycemia (13.2 ± 0.82 mmol/L), increased plasmatic insulin levels (25.10 ± 2.12 U/L) and HOMA-IR index (14.72 ± 0.85) accompanied with dyslipidemia, elevation of hepatic enzyme levels, and a change in both serum renal biomarkers and plasmatic calcium. The co-administration of propolis and bee pollen extracts alone or in combination restored these biochemical parameters and attenuated the deleterious effects of D-glucose on liver and kidney functions. Furthermore, these effects were better attenuated in the combined therapy-prevented diabetic rats. Hence, it is possible to conclude that propolis and bee pollen can be used as a preventive natural product against diabetes induced dyslipidemia and hepato-renal damage.

Beneficial Effects of Apple Vinegar on Hyperglycemia and Hyperlipidemia in Hypercaloric-Fed Rats

The main objective of this study is to determine the effects of apple vinegar on the metabolic changes caused by hypercaloric diet in Wistar rats. Apple vinegar was first analyzed to find out the total acidity, the polyphenolic and flavonoid contents, the total antioxidant capacity, and the free radical scavenging activity. In vivo study on adult male and female Wistar rats was conducted by administering a drink containing either 10% D-glucose or water (control) for five weeks. Apple vinegar is administered daily by gavage (2 mL/kg) to rats fed D-glucose for 5 weeks. The results showed that the polyphenolic content in apple vinegar was 148.02 ± 10.16 mg GAE/100 mL, flavonoid content was 22.93 ± 0.73 QE/100 mL, and total antioxidant capacity was 13.4 ± 0.47 mg AAE/100 mL. Free radical IC₅₀ apple vinegar scavenging activity (DPPH) was 0.74 ± 0.154 μL/mL. The total acidity was (3.24 ± 0.02 mg AAE/100 mL). The treatment during five weeks with D-glucose leads to increased plasma glucose, lipid profile, hepatic enzyme levels, urea, and creatinine. Simultaneous treatment with apple vinegar improves the parameters studied. These results clearly show that the daily consumption of vinegar can reduce the rise in blood sugar and lipid profile induced by hypercaloric diet in rats. Therefore, the use of apple vinegar would have a very beneficial effect in the prevention of metabolic disorders caused by high-caloric food.