Effects of Royal Jelly Administration on Lipid Profile, Satiety, Inflammation, and Antioxidant Capacity in Asymptomatic Overweight Adults.

OBJECTIVES: Obesity and overweight are chronic disorders of multifactorial origin that are characterized by high oxidative status and by chronic activation of macrophages in peripheral tissues. Effective therapeutic approaches to lower inflammation and oxidative stress are currently of general interest. Royal jelly (RJ) is a functional food with a broad range of pharmacological activities, mainly used by healthy individuals or borderline patients to protect themselves against disease onset. The objective of this randomized, double-blind, placebo-controlled trial was to investigate the effects of RJ supplementation on metabolic profile and oxidative and inflammatory parameters in asymptomatic overweight adults, considered at an early stage of developing metabolic syndrome. MATERIAL AND METHODS: The experimental group (n=30) was given RJ and the control group (n=30) was provided with a placebo for eight weeks. Anthropometric, biochemical parameters, biomarkers of oxidative stress, and inflammation were assessed at baseline, after 4 and 8 weeks of the intervention, and after additional 2 weeks of follow up. RESULTS AND CONCLUSION: Compared with the placebo, RJ supplementation demonstrated a statistically significant decrease in total cholesterol (6.7%; p=0.041) and inflammatory marker C-reactive protein (19%; p=0.027), whereas significant increases were observed in anti-inflammatory marker adiponectin (34%; p=0.011), endogenous antioxidants bilirubin (35%; p=0.002) and uric acid (5%; p=0.018), total antioxidant capacity in serum (54%; p=0.005), and leptin (17%; p=0.025). The present study demonstrated positive effects of RJ administration on lipid profile, satiety, inflammation, and antioxidant capacity in overweight adults. Therefore, our study supports the benefits of RJ supplementation for the improvement of human health.

Band smearing of PCR amplified bacterial 16S rRNA genes: dependence on initial PCR target diversity.

Band smearing in agarose gels of PCR amplified bacterial 16S rRNA genes is understood to comprise amplicons of varying sizes arising from PCR errors, and requires elimination. We consider that with amplified heterogeneous DNA, delayed electro-migration is caused not by PCR errors but by dsDNA structures that arise from imperfect strand pairing. The extent of band smearing was found to be proportional to the sequence heterogeneity in 16S rRNA variable regions. Denaturing alkaline gels showed that all amplified DNA was of the correct size. A novel bioinformatic approach was used to reveal that band smearing occurred due to imperfectly paired strands of the amplified DNA. Since the smear is a structural fraction of the correct size PCR product, it carries important information on richness and diversity of the target DNA. For accurate analysis, the origin of the smear must first be identified before it is eliminated by examining the amplified DNA in denaturing alkaline gels.

Antibiotic susceptibility profile of Mycobacterium avium subspecies hominissuis is altered in low-iron conditions.

OBJECTIVES: Antibiotic susceptibility testing of the Mycobacterium avium complex is often characterized by a lack of correlation between in vitro results and clinical response. The reason for this discrepancy might lie in the difference between in vitro susceptibility testing conditions and the actual environment experienced by mycobacteria in the host. The availability of iron is one such difference, which is limited in host macrophages upon infection, but abundant in susceptibility testing media. Accordingly, the aim of our study was to determine whether iron limitation affects the antibiotic susceptibility profile of M. avium subspecies hominissuis. METHODS: Susceptibilities to multiple antibiotics targeting various cellular processes were determined in media with normal- and low-iron concentrations using the resazurin microplate assay. Differences in susceptibilities were evaluated by monitoring changes in the MIC and growth inhibition at subinhibitory antibiotic concentrations (sub-MICs). RESULTS: Cultures grown in low-iron conditions were less susceptible to the DNA synthesis inhibitors 6-mercaptopurine and levofloxacin at sub-MICs. Decreased susceptibility to the protein synthesis inhibitors azithromycin (>2-fold) and streptomycin (at sub-MICs) was observed only during adaptation to low-iron conditions. On the contrary, increased susceptibility to antibiotics that interfere with cell wall synthesis [isoniazid (4-fold), d-cycloserine (2-fold) and ethambutol (at sub-MICs)], mycobactin synthesis [4-aminosalicylate (at sub-MICs)] and mRNA synthesis [rifampicin (4-fold)] was observed in low-iron conditions. CONCLUSIONS: The susceptibility profile in low-iron conditions significantly differs from that observed in normal-iron conditions. Mimicking the host environment in terms of iron availability should be considered for in vitro susceptibility testing of mycobacteria, especially for antibiotics interfering with iron metabolism, such as 4-aminosalicylate.

Evaluation of combined high-efficiency DNA extraction and real-time PCR for detection of Mycobacterium avium subsp. paratuberculosis in subclinically infected dairy cattle: comparison with faecal culture, milk real-time PCR and milk ELISA.

BACKGROUND: Johne's disease is caused by Mycobacterium avium subsp. paratuberculosis (Map) and it is one of the most important diseases in cattle worldwide. Several laboratory tests for Map detection are available; however, these are limited by inadequate sensitivity and specificity when used in subclinically infected populations. To identify Map shedders in subclinically infected cattle, we used a new, high-yield method for DNA-extraction from Map in faeces combined with quantitative real-time PCR (qPCR) for amplification of the insertion sequence IS900 of Map (HYDEqPCR). Evaluation of HYDEqPCR was carried out in comparison with faecal culture, milk qPCR, and milk enzyme-linked immunosorbent assay (ELISA), on 141 faecal and 91 milk samples, from 141 subclinically infected dairy cattle. RESULTS: The qPCR proved to be highly sensitive, with a detection limit of 2 IS900 DNA copies/µl in 67 % of the reactions. It also showed 100 % specificity, as determined from 50 Map and non-Map strains, and by the sequencing of qPCR amplicons. The detection limit of HYDEqPCR was 90 Map/g Map-spiked faeces, which corresponds to 2.4 colony forming units/g Map-spiked faeces, with an estimated efficiency of 85 % (±21 %). When tested on the field samples, HYDEqPCR showed 89 % of the samples as positive for Map, whereas faecal culture, milk qPCR, and milk ELISA detected 19 %, 36 % and 1 %, respectively. Fisher's exact tests only show statistical significance (p ≤0.05) for the correlation between HYDEqPCR and faecal culture. The agreement between HYDEqPCR and milk qPCR and milk ELISA was poor, slight, and non-significant. CONCLUSIONS: This study highlights the advantages of HYDEqPCR for detection of Map in subclinically infected populations, in comparison with faecal culture, milk qPCR and milk ELISA. HYDEqPCR can detect low-level Map shedders that go undetected using these other methods, which will thus underestimate the proportions of Map-shedders in herds. Identification of these shedding animals is extremely important for prevention of the spread of Map infection in an animal population. Due to the relatively high sensitivity and specificity of HYDEqPCR, it can be applied to test for Map at the herd or individual level, regardless of animal age or production stage. HYDEqPCR will allow early detection and control of Map in any population at risk.