Effects of metformin on prostatic tissue of rats with metabolic syndrome and benign prostatic hyperplasia

Integrated high-throughput analysis identifies super enhancers in metastatic castration-resistant prostate cancer

Background: Metastatic castration-resistant prostate cancer (mCRPC) is a highly aggressive stage of prostate cancer, and non-mutational epigenetic reprogramming plays a critical role in its progression. Super enhancers (SE), epigenetic elements, are involved in multiple tumor-promoting signaling pathways. However, the SE-mediated mechanism in mCRPC remains unclear. Methods: SE-associated genes and transcription factors were identified from a cell line (C4-2B) of mCRPC by the CUT&Tag assay. Differentially expressed genes (DEGs) between mCRPC and primary prostate cancer (PCa) samples in the GSE35988 dataset were identified. What's more, a recurrence risk prediction model was constructed based on the overlapping genes (termed SE-associated DEGs). To confirm the key SE-associated DEGs, BET inhibitor JQ1 was applied to cells to block SE-mediated transcription. Finally, single-cell analysis was performed to visualize cell subpopulations expressing the key SE-associated DEGs. Results: Nine human TFs, 867 SE-associated genes and 5417 DEGs were identified. 142 overlapping SE-associated DEGs showed excellent performance in recurrence prediction. Time-dependent receiver operating characteristic (ROC) curve analysis showed strong predictive power at 1 year (0.80), 3 years (0.85), and 5 years (0.88). The efficacy of his performance has also been validated in external datasets. In addition, FKBP5 activity was significantly inhibited by JQ1. Conclusion: We present a landscape of SE and their associated genes in mCPRC, and discuss the potential clinical implications of these findings in terms of their translation to the clinic.

Simvastatin inhibits prostatic hyperplasia in rats with metabolic syndrome

OBJECTS

To evaluate the influence of metabolic syndrome (MetS) induced by high fat diet (HFD) on prostate tissue and local inflammatory factors in rats model, and the protective efficacy of statins against pathological changes of prostate.

METHODS

40 Sprague-Dawley rats were divided into 4 subgroups of normal diet (ND), HFD blank, HFD + saline and HFD + simvastatin. After the establishment of models, all subjects were killed to obtain body weight serum lipid, FBG level, FINS and HOMA-IR level. Hyperplasia level of prostate, as well as expression level of interleukin 6 (IL-6), insulin-like growth factor 1 (IGF-1), interleukin 10 (IL-10) and tumor necrosis factor alpha (TNF-α) were also measured.

RESULTS

Models have been successfully established. Level of serum lipid, prostatic weight, hyperplasia as well as expressions of IL-6, TNF-α and IGF-1 in the blank and saline subgroups of HFD group were higher than that of ND group (P < 0.05). While simvastatin has significantly resisted the former effects of HFD on serum lipid and prostate (P < 0.05). No significant difference in serum FBG level was found between groups and subunits. FINS levels of ND group was lower than other groups (P < 0.05). In addition, There is no significant difference in FPG and HOMA-IR levels in blank control subunit, saline control subunit, simvastatin subunit (P > 0.05).

CONCLUSIONS

MetS induced by HFD is an important factor in the induction of BPH. Simvastatin can alleviate the hyperplasia of prostate through the relief of local inflammation in prostatic tissue.

Aerobic exercises ameliorate benign prostatic hyperplasia via IGF-1/IGF-1R/ERK/AKT signalling pathway in prostate tissue of high-fat-diet-fed mice with insulin resistance

This study investigated the changes in the prostate of high-fat diet (HFD)-fed mice with insulin resistance (IR) and explored the possible mechanisms of the effects of 8-week treadmill aerobic exercise on prostatic hyperplasia in insulin-resistant mice through the IGF-1/IGF-1R/ERK/AKT signalling pathway. Results showed IR in mice caused an increase in prostate-related indicators, such as prostate weight (PW) and prostate volume (PV), resulting in prostatic hyperplasia. The area of the glandular lumen and the height of the glandular epithelium in mice with IR were increased, which indicating that it caused prostatic hyperplasia through epithelial cell proliferation. In addition, the level of IGF-1 in serum and the expression of IGF-1R, ERK and AKT in prostate tissue of high-fat diet induced IR mice increased significantly, which might be related to the proliferation of prostate cells. However, aerobic exercise lowered the blood sugar, serum insulin and IGF-1; inhibited the combination of IGF-1 and IGF-1R on the prostate; down-regulated the expression of IGF-1R, ERK and AKT proteins; and then suppressed the expression of downstream proliferation genes, thereby achieving the purpose of inhibiting the proliferation of prostate epithelial cells. In conclusion. Eight weeks of aerobic exercise might improve the prostate hyperplasia in mice via down-regulating the serum insulin and IGF-1, thus enhancing the insulin sensitivity of insulin-resistant mice and regulating the IGF-1/IGF-1R/ERK/AKT signalling pathway by inhibiting the expression of IGF-1R, ERK and AKT in the prostate tissue. However, this exercise had no significant effect on PV, PW and prostate index (PI).

High-Fat Diet Induced Gut Microbiota Alterations Associating With Ghrelin/Jak2/Stat3 Up-Regulation to Promote Benign Prostatic Hyperplasia Development

The role of high-fat diet (HFD) induced gut microbiota alteration and Ghrelin as well as their correlation in benign prostatic hyperplasia (BPH) were explored in our study. The gut microbiota was analyzed by 16s rRNA sequencing. Ghrelin levels in serum, along with Ghrelin and Ghrelin receptor in prostate tissue of mice and patients with BPH were measured. The effect of Ghrelin on cell proliferation, apoptosis, and induction of BPH in mice was explored. Our results indicated that BPH mice have the highest ratio of Firmicutes and Bacteroidetes induced by HFD, as well as Ghrelin level in serum and prostate tissue was significantly increased compared with control. Elevated Ghrelin content in the serum and prostate tissue of BPH patients was also observed. Ghrelin promotes cell proliferation while inhibiting cell apoptosis of prostate cells. The effect of Ghrelin on enlargement of the prostate was found almost equivalent to that of testosterone propionate (TP) which may be attenuated by Ghrelin receptor antagonist YIL-781. Ghrelin could up-regulate Jak2/pJak2/Stat3/pStat3 expression in vitro and in vivo. Our results suggested that Gut microbiota may associate with Ghrelin which plays an important role in activation of Jak2/Stat3 in BPH development. Gut microbiota and Ghrelin might be pathogenic factors for BPH and could be used as a target for mediation.

The Effect of Metformin on Male Reproductive Function and Prostate: An Updated Review

Metformin is the first-line oral antidiabetic drug that shows multiple pleiotropic effects of anti-inflamation, anti-cancer, anti-aging, anti-microbia, anti-atherosclerosis, and immune modulation. Metformin's effects on men's related health are reviewed here, focusing on reproductive health under subtitles of erectile dysfunction (ED), steroidogenesis and spermatogenesis; and on prostate-related health under subtitles of prostate specific antigen (PSA), prostatitis, benign prostate hyperplasia (BPH), and prostate cancer (PCa). Updated literature suggests a potential role of metformin on arteriogenic ED but controversial and contradictory effects (either protective or harmful) on testicular functions of testosterone synthesis and spermatogenesis. With regards to prostate-related health, metformin use may be associated with lower levels of PSA in humans, but its clinical implications require more research. Although there is a lack of research on metform's effect on prostatitis, it may have potential benefits through its anti-microbial and anti-inflammatory properties. Metformin may reduce the risk of BPH by inhibiting the insulin-like growth factor 1 pathway and some but not all studies suggest a protective role of metformin on the risk of PCa. Many clinical trials are being conducted to investigate the use of metformin as an adjuvant therapy for PCa but results currently available are not conclusive. While some trials suggest a benefit in reducing the metastasis and recurrence of PCa, others do not show any benefit. More research works are warranted to illuminate the potential usefulness of metformin in the promotion of men's health.

Diagnostic Criteria for Metabolic Syndrome in Diet-Induced Rodent Models: A Systematic Review

BACKGROUND

Thousands of publications in recent years have addressed the induction of metabolic syndrome (MetS) in rodents. However, the criteria and the reference values for diagnosing this disease have not been defined.

OBJECTIVE

Our main objective was to carry out a systematic review to gather evidence about the criteria for biochemical and anthropometric parameters in which scientific studies have relied on to report that rats developed MetS from a previous dietary manipulation.

METHODS

We compiled characteristics and findings of diet-induced MetS with high-fat, high-carbohydrate, high-fat/high-carbohydrates, and cafeteria diet from PubMed and Science Direct databases published in the last 5 years.

RESULTS

The results on the principal determinants for the syndrome, published in the reviewed articles, were chosen to propose reference values in the rat models of food induction.

CONCLUSION

The values obtained will serve as reference cut-of points in the development of the disease; in addition, the compilation of data will be useful in planning and executing research protocols in animal models.

The relationship between glucose homeostasis status and prostate size in aging Chinese males with benign prostatic hyperplasia

PURPOSE

Increasing evidence shows that many metabolic factors are involved in the progression of benign prostatic hyperplasia (BPH). We aimed to assess the relationship between the status of glucose homeostasis and prostate size in aging Chinese males undergoing transurethral resection of the prostate (TURP) for BPH.

METHODS

A total of 1006 medical records of BPH patients undergoing TURP were reviewed. Prostate size was measured by transrectal ultrasound. Annual total prostate (TP) and transitional zone (TZ) growth rates were calculated. According to the American Diabetes Association criteria, the patients were categorized as normoglycemic, prediabetic, or diabetic. Levels of glucose homeostasis and other variables were considered independent variables in an effort to evaluate any potential correlations using non-adjusted and multivariate-adjusted regression models.

RESULTS

A total of 659 individuals were included in the study. BPH patients < 70 years old and ≥ 70 years old in the normoglycemic group had a stable prostate growth rate. The change in prostate size in those younger than 70 years, however, was faster in the prediabetic and diabetic group. Further analysis revealed that abnormal glucose homeostasis was positively correlated with prostate size. In those younger than 70 years, compared with the normal glucose group, the adjusted odds ratio (OR) for TP and TZ enlargement in the prediabetic group was 2.27 (95%CI 1.29-4.00) and 3.19 (95%CI 1.78-5.72), respectively, and the adjusted ORs were 4.74 (95%CI 2.18-10.30) and 6.16 (95%CI 2.70-14.06), respectively, for men with diabetes. However there was no significant difference among men aged ≥ 70 years.

CONCLUSIONS

Among patients undergoing TURP, the prostate volume and growth rate were affected by different status of glucose homeostasis. Hyperglycemia may play an important role in prostate growth.

Animal models of benign prostatic hyperplasia

Benign prostatic hyperplasia (BPH) and associated lower urinary tract symptoms are common clinical concerns that affect aging men all over the world. The underlying molecular and cellular mechanisms remain elusive. Over the past few years, a number of animal models of BPH, including spontaneous model, BPH-induction model, xenograft model, metabolic syndrome model, mechanical obstruction model, and transgenic model, have been established that may provide useful tools to fill these critical knowledge gaps. In this review, we therefore outlined the present status quo for animal models of BPH, comparing the pros and cons with respect to their ability to mimic the etiological, histological, and clinical hallmarks of BPH and discussed their applicability for future research.