Inflammation is a generalized histopathologic finding of BPH (Fibbi et al. 2010; Schauer and Rowley 2011) and is associated with a higher risk of lower urinary tract symptoms (LUTS) (Kramer and Marberger 2006) and acute urinary retention in aging men (Nickel et al. 2008). Recent studies have shown an increased risk of BPH in patients proven to have prostate inflammation on biopsy examination (Crawford et al. 2006). In prostate tissue developing hyperplasia, inflammation can induce proliferation events and nuclear deterioration through cytokines and oxidative stress (Naber and Weidner 2000). The aggressive release of oxygen radicals from macrophages and neutrophils during acute or chronic inflammation may lead to compensatory cellular proliferation, which further exacerbates oxidative stress, and in such conditions, hyperplastic proliferation may occur in the prostate tissue (Vital et al. 2015). Tanik et al. (2014) used inflammatory parameters like the neutrophil-to-lymphocyte ratio to predict BPH progression and LUTS severity and found a positive correlation between the neutrophil count and prostate hyperplasia.
High-fat diets (HFD) have also been implicated in oxidative stress and inflammation in the prostate gland (Shankar et al. 2012) as they increase the levels of acute-phase inflammatory markers (Kriketos et al. 2004) via cytokines released from neutrophils and macrophages in adipose tissue (Shankar et al. 2015). Using a HFD-induced metabolic syndrome animal model with hyperglycemia, dyslipidemia, and hypogonadism, Vignozzi et al. (2012) linked metabolic syndrome to prostate inflammation, and found that it was correctible with testosterone replacement. Like HFD, DM has also been linked to chronic inflammatory conditions, and it has been implicated in increasing cytokine levels, mostly in the adipose tissue (Gibb and Strachan 2014). Further, DM-related androgen deficiency has been observed in a third of the population with type 2 diabetes, although the underlying mechanism remains unclear (Cheung et al. 2015; Morton 2005). The prostate volume has been found to be especially high in male patients diagnosed with type 2 diabetes (Kasturi et al. 2006), and in the NHANES-3 cohort study, Rohrman et al. observed a higher incidence of BPH in men with diabetes than in those without diabetes (American Diabetes Association 1998). Our results confirmed the effects of DM on prostate tissue shown in previous literature. A continuous supply of androgen is crucial for the growth and normal functioning of the prostate gland, and when this supply stops or decreases, prostate disease may develop (Yadav and Heemers 2012).
Rahman et al. (2000) conducted a detailed chemical examination of B. chrysogonum and examined the effects of saponins extracted from these tubers. Saponins are fat- and water-soluble glycosides with glycan or aglycan structures. In the intestine, saponins form micelles with bile acids, vitamins, fat acids, and diglycerides. Several studies have shown that because of a reduction in surface tension and detergent effects in the gastrointestinal tract, saponins reduce the emulsification of fat molecules and bile acids (Rao and Kendall 1986; Sidhu and Oakenfull 1986; Whitehead et al. 1981). Further, Bingham et al. (1978) showed that although saponins decreased the serum cholesterol and liver lipid concentrations, the liver cholesterol and serum HDL levels remain unchanged. The findings of our study agree with those of previous studies, as we clearly observed the anti-cholesterolemic and anti-lipidemic effects of B. chrysogonum in the blood and liver, respectively. Further, the testosterone levels in group D of the present study were significantly lower than those in group DB. These findings indicate that the hypogonadal status induced by DM was ameliorated by administration of B. chrysogonum. Additionally, correction of the deficiency in testosterone levels, which exacerbates prostate inflammation and tissue remodeling, may prevent or at least decelerate the course of BPH.
Arslan et al. (2005) and Assaf et al. (2013) studied the effects (Fig. 3) of B. chrysogonum on various tissues under certain conditions. However, to our knowledge, ours is the first study to histologically examine its effects on prostate tissues in DM.
Histologically at the cellular level, BPH is characterized by basal cell hyperplasia, increased stromal mass, enhanced extracellular matrix deposition, reduced elastic tissue, increased infiltration of leucocytes around ducts, and acinar hypertrophy (Bostwick et al. 1992).
The accumulation of inflammation throughout the prostatic tissue aggravates the process of prostatic hyperplasia by enhancing the production of prostatic growth factors. Furthermore, the altered secretion of luminal cells and clogging of the ducts with debris and corpora amylacea may lead to prostatic calcification, which is a significant modification of the hyperplastic prostate. Our findings showed that the conditions of the prostate tissue were better in rats with diabetes who were treated with B. chrysogonum than in those that were not treated with this herb: as mentioned in the “Results” section, the epithelium was better preserved and less debris was seen in the glandular lumen in group DB than in group D. Further, the TOS levels were significantly higher in group D than group DB, while the OSI levels were significantly lower.
Chronic conditions such as DM and hypercholesterolemia require lifelong treatment, and patient compliance may be better with alternative herbal treatment options in the case of such conditions. As indicated by our findings, the well-known plant B. chrysogonum seems to have positive effects on glucose and lipid metabolism. Further, it seems to prevent the pathological changes that occur in the prostate tissue in DM. Thus, this herb may be a useful treatment option for patients with DM and BPH. Further molecular studies are needed to confirm the effects of B. chrysogonum on the prostate tissue and to develop this herb into an effective therapeutic agent against DM and BPH.