Hypothesis / aims of study
It is well known that acute and chronic prostatitis causes male lower urinary tract syndrome. Non-bacterial prostatitis (NBP) is the frequent disease of prostatic imflammation disease group. The prevalence of symptomps suggestive of prostatitis ranges between 2.2% and 13.8% according to different studies. However, the etiology of NBP is still unknown. Althogh several types of medicines, such as alpha-adrenergic blockers, nonsteroidal anti-inflammatory drugs (NSAIDs) and Long-term antibiotics may be used, the NBP is hard to cure.
The pollen extract Cernitin contains 63mg pollen extract. It is essentially a microbial digest of a standardized mixture of eight plant species grown at the Scania area in southern Sweden. The active ingredients consist of water-soluble (T-60) and fat-soluble (GBX) fractions. It was reported that cernitin showed urine discharge action, anti-prostatic hypertrophic action and anti-inflammatory effects to the prostate in a preliminary study.
To assess the mechanisms of the anti-prostatitis effect by cernitin, this study was performed using a non-bacterial prostatitis rat model induced by 5% formalin injection into prostate.
Furthermore, using Liquid Chromatograph-tandem Mass Spectrometer (LC-MS/MS), cernitin GBX ingredients were analyzed to determine the effective lipid mediator.
Study design, materials and methods
Male SD rats were randomly assigned to the following groups: sham - vehicle (n=4), formalin - vehicle (n=4), formalin - cernitin T60 (n=4), formalin - cernitin GBX (n=4), formalin - cernitin T60+GBX (n=4).
Sham-vehicle group had sham operations and was injected with 50 μl saline into bilateral ventral lobes of the prostate. The formalin groups rats were injected with 5% formalin solution at a volume of 50 μl into bilateral ventral lobes of the prostate. The formalin-treatment groups were treated with T-60 (1,200mg/kg), GBX (60mg/kg), and T-60+GBX (1260mg/kg) daily from 2 days before intra-prostatic formalin injection for 9 days.
At day8, after the metabolic cage, the ventral lobes of the prostate were harvested for evaluation of inflammatory mRNA expression and histological analysis.
To determine the effective ingredients, cernitin GBX was analyzed with LC-MS/MS of lipid mediator.
Results
The mean voiding intervals were significantly shorter and the mean voiding volume was significantly decreased in formalin - vehicle rats than those in sham - vehicle rats (p<0.05). In contrast, those in formalin - cernitinT60+GBX rats were improved compared with formalin - vehicle rats.
In RT-qPCR analysis, inflammatory mRNA expression such as IL-1β, IL-6 and NLRP3 were significantly increased in formalin - vehicle rats compared with sham - vehicle rats (p<0.05). However, mRNA expression of those in formalin - cernitin T60, formalin - cernitin GBX and formalin - cernitin T60+GBX rats were significantly decreased compared with formalin - vehicle rats. The improvement rate of inflammatory cytokines was cernitin T60+GBX, cernitin GBX and cernitin T60 in descending order.
In hematoxylin eosin and masson-trichrome stain, inflammatory cells and fibrosis were increased in prostatic stroma of formalin - vehicle rats compared with sham - vehicle rats. In contrast, those of formalin - cernitin groups were not remarkable.
In LC-MS/MS, cernitin GBX was contained several lipid mediators such as Oleoylethanolamide (OEA), 9-HOTrE and 13-HOTrE, which are reported of anti-inflammatory effect.
Interpretation of results
Cernitin T60 and Cernitin GBX improved prostatic inflammation in rat model. As a result, the voiding interval and voiding volume of prostatic inflammation rats were ameliorated with formalin - Cernitin groups' rats.
OEA and HOTrEs, the main lipid mediator contained in cernitin GBX, could play a key role of anti-inflammatory effect according to the reports in inflammatory disorder such as SLE and rheumatic disease.