Screening of Plant Pollen Sources, Polyphenolic Compounds, Fatty Acids and Antioxidant/Antimicrobial Activity from Bee Pollen

In this study, the botanical origin, total flavonoid and phenolic content, antioxidant activity, phenolic profile and fatty acid composition of mixed bee pollen loads collected in Bayburt, Turkey, were determined. In addition to these assays, antibacterial activity of bee-collected pollen extract (BCPE) against a variety of food-borne pathogenic bacteria was determined in vitro. Pollen loads were classified into five botanical families based on their color: Asteraceae, Fabaceae, Campanulaceae, Cistaceae and Rosaceae. Total flavonoid, total phenolic, CUPRAC and CERAC concentrations were 173.52 mg GAE/g, 79.21 mg QE/g, 85.59 mg Trolox/g and 118.13 mg Trolox/g, respectively. Twenty-three phenolic compounds were scanned in bee pollen extract by LC-MS/MS, with rutin being the most abundant. Cis-4,7,10,13,16,19 docosahexaenoic acid was the predominant fatty acid, followed by cis-11-eicosenoic acid, palmitic acid, and alfa linolenic acid. In addition, the agar well diffusion (AWD) and micro-broth dilution methods were used to determine of the antibacterial activity of the BCPE sample. MIC values were observed to vary between 2.5–5 mg/mL for Gram-positive bacteria and 5–10 mg/mL for Gram-negative bacteria. These findings indicate that bee pollen could be a potential source of antioxidants and antimicrobials.

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. Ten groups of male Wistar rats were treated with EG, cystone (500 mg/kg) or BPE at doses 100, 250, and 500 mg/ kg. 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 pH, volume, calcium, phosphorus, uric acid, and protein, and blood urea, creatinine, and liver enzymes (P<0.05). It 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, and proteinuria, and stone deposition, most likely by its antioxidant content and activity.

Allergenicity to worldwide invasive grass Cortaderia selloana as environmental risk to public health

Allergies to grass pollen affects about 20% of the population worldwide. In the last few decades, the South American grass Cortaderia selloana (CS, Pampas grass) has expanded worldwide in a variety of countries including the USA, Australia and Western Europe. In many of these locations, CS has strikingly spread and has now been classified an invasive species. Many pernicious consequences of CS have been reported for local biodiversity, landscape and structures. However, the effect on human health has not been studied. To investigate this issue, we have chosen a European region on the northern cost of Spain where CS spread is overwhelming, Cantabria. We obtained CS pollen extract and analysed the allergenic reaction of 98 patients that were allergic to pollen of local grasses. We determined the skin reaction and the presence of specific IgE antibodies (sIgE) to CS or to a typical autochthonous grass, Phleum pratense. We also compared the seasonal symptoms with reported grass pollen counts in the area. The results strongly suggest that CS can cause respiratory allergies at a similar extent to the local grasses. Given that CS pollinises later than the local grasses, this would extend the period of grass allergies in the region for about three months every year, as stated by most of the patients. This is the first study reported on the effects of the striking expansion of CS on human health. Considering the strong impact that respiratory allergies have on the population, our results suggest that CS can currently constitute a relevant environmental health issue.

Differential Bumble Bee Gene Expression Associated With Pathogen Infection And Pollen Diet

Background: Diet and parasitism can have powerful effects on host gene expression. However, how specific dietary components affect host gene expression that could feed back to affect parasitism is relatively unexplored in many wild species. Recently, it was discovered that consumption of sunflower (Helianthus annuus) pollen reduced severity of gut protozoan pathogen Crithidia bombi infection in Bombus impatiens bumble bees. Despite the dramatic and consistent medicinal effect of sunflower pollen, very little is known about the mechanism(s) underlying this effect. However, sunflower pollen extract increases rather than suppresses C. bombi growth in vitro, suggesting that sunflower pollen reduces C. bombi infection indirectly via changes in the host. Here, we analyzed whole transcriptomes of B. impatiens workers to characterize the physiological response to sunflower pollen consumption and C. bombi infection to isolate the mechanisms underlying the medicinal effect. B. impatiens workers were inoculated with either C. bombi cells (infected) or a sham control (un-infected) and fed either sunflower or wildflower pollen ad libitum. Whole abdominal gene expression profiles were then sequenced with Illumina NextSeq 500 technology. Results: Among infected bees, sunflower pollen upregulated immune transcripts, including the anti-microbial peptide hymenoptaecin, Toll receptors and serine proteases. In both infected and un-infected bees, sunflower pollen upregulated putative detoxification transcripts and transcripts associated with the repair and maintenance of gut epithelial cells. Among wildflower-fed bees, infected bees downregulated immune transcripts associated with phagocytosis and the phenoloxidase cascade. Conclusions: Taken together, these results indicate dissimilar immune responses between sunflower- and wildflower-fed bumble bees infected with C. bombi, a response to physical damage to gut epithelial cells caused by sunflower pollen, and a strong detoxification response to sunflower pollen consumption. Identifying host responses that drive the medicinal effect of sunflower pollen in infected bumble bees may broaden our understanding of plant-pollinator interactions and provide opportunities for effective management of bee pathogens.

Potential Activity of Abrantes Pollen Extract: Biochemical and Cellular Model Studies

The aim of this study was to determine the grain composition and (poly)phenolic profile of pollen from Abrantes (Portugal), as well as its antioxidative and antidiabetic properties, and abilities to protect human erythrocytes against induced hemoglobin oxidation, lipid peroxidation, and hemolysis. The phytochemical profile of the Abrantes’ bee pollen revealed twenty phenolic compounds, identified by high-performance liquid chromatography with electrospray ionization mass spectrometry coupled with photodiode array detection. Among them, quercetin derivatives were the most abundant. Concerning the biological potential, the pollen extract showed notable capacity for 2,2-diphenyl-1-picrylhydrazyl, nitric oxide, and superoxide radicals, as well as for inhibition of α-glucosidase action, and protection of human erythrocytes against oxidative damage. Non-cytotoxic effects regarding the NHDF normal cell line, human adenocarcinoma Caco-2, and human liver HepG2 cells were observed. The results obtained contributed to further research on modes of action related to oxidative damage and metabolic health problems, to generate deeper knowledge of potential health-promoting effects to develop novel pharmaceutical drugs, nutraceuticals, and dietary supplements.

Plant Food Allergy Improvement after Grass Pollen Sublingual Immunotherapy: A Case Series

Background: Cross-reactivity between pollens and plant food has been widely described. Pollen extract subcutaneous immunotherapy in patients with pollens and plant food allergy has been shown to improve tolerance not only to inhalant allergens but also to reduce symptoms in patients with various food allergies. Methods: We retrospectively report our experience with 15 female patients with a positive history for moderate, persistent allergic rhinitis due to grass pollen and oropharyngeal symptoms after ingestion of different plant food. These patients followed a five-grass pollen sublingual tablet immunotherapy for three years in a discontinuous pre-co-seasonal scheme. Results: All 15 patients treated with the 5-grass pollen sublingual tablet immunotherapy, taken once daily for 3 years on a 7-month course, showed improved ocular/nasal symptoms, with a reduction in the use of symptomatic drugs (e.g., nasal corticosteroids and H1 antihistamines). After the first seven-month course of immunotherapy, all patients declared a good tolerance to the intake of fruits and vegetables, and in particular, good tolerance to the offending foods. Conclusions: In conclusion, we have observed improvement of both respiratory and plant food allergies after sublingual immunotherapy (SLIT) with a five-grass pollen tablet.