Chemopreventive Effect of Cinnamon and Its Bioactive Compounds in a Rat Model of Premalignant Prostate Carcinogenesis.

Cinnamon and its bioactive compounds inhibit prostate cancer cell proliferation in vitro. The aim of the current study was to assess the chemopreventive efficacy of cinnamon (CN) and its bioactive compounds in vivo using N-methyl-N-nitrosourea (MNU) and testosterone (T) to induce prostate carcinogenesis in male Wistar/National Institute of Nutrition rats. Cancer-induced (CI) rats (n = 10) developed prostatic hyperplasia and prostatic intraepithelial neoplasia. These histopathologic changes were diminished in CI rats fed for 4 months with diets supplemented with either CN (n = 20) or its bioactive compounds (cinnamaldehyde, n = 10 and procyanidin B2, n = 10). Androgen receptor (AR) expression was lower in the prostates of CI rats than in control, but the AR target gene, probasin, was robustly upregulated. Treatment of CI rats with CN or its bioactive compounds upregulated AR expression but inhibited the expression of the 5-alpha reductase genes (Srd5a1 and Srd5a2) and did not further increase probasin expression, suggesting blunted transcriptional activity of AR due to the limited availability of dihydrotestosterone. MNU+T induced an altered oxidant status in rat prostate, which was reflected by an increase in lipid peroxidation and DNA oxidation. These changes were completely or partially corrected by treatment with CN or the bioactive compounds. CN and its active components increased the activity of the apoptotic enzymes caspase-8 and caspase-3 in the prostates of CI rats. In conclusion, our data demonstrate that CN and its bioactive compounds have inhibitory effects on premalignant prostate lesions induced by MNU + T and, therefore, may be considered for the chemoprevention of prostate cancer. PREVENTION RELEVANCE: The research work presented in this article demonstrates the chemopreventive efficacy of CN and its bioactive compounds in a rat model of premalignant prostate cancer.

[Chemoprevention of prostate cancer - a plea]. / Chemoprävention des Prostatakarzinoms - Ein Plädoyer.

The high disease prevalence, the presentation in older age, a frequently slowly progressing course of disease, and high costs make the diagnosis of and therapy for prostate cancer a special challenge for urologists. Effective prevention of the disease may help to improve some of the problems mentioned above. Two randomised, controlled studies have proved that effective chemoprevention of prostate cancer is viable using 5α-reductase inhibitors (finasteride, dutasteride). Furthermore, there is increasing evidence that other compounds, e. g., selective oestrogen receptor modulators (SERMs), NSAIDs and statins might also be effective. This review investigates potential risks and benefits of chemoprevention including a consideration of health economical aspects. The authors conclude that the options of chemoprevention should be investigated in an open and unbiased way.

A review of combination therapy in patients with benign prostatic hyperplasia.

BACKGROUND: Trials of monotherapy with alpha(1)-adrenergic-receptor antagonists (alpha(1)ARAs) and 5 alpha-reductase inhibitors (5ARIs) have found that the former drug class is effective in managing benign prostatic hyperplasia (BPH)-related lower urinary tract symptoms (LUTS) and improving the maximal urinary flow rate in shortand long-term treatment, regardless of prostate size, whereas the latter drug class is effective in reducing prostate size and preventing disease progression in longer-term treatment. The differing mechanisms of action and areas of efficacy of these 2 drug classes make them promising candidates for combination therapy. OBJECTIVE: This article reviews key trials of monotherapy and combination alpha(1)ARV5ARI therapy in the treatment and prevention of BPH-related voiding dysfunction. METHODS: MEDLINE (1976-2006) and the Cochrane Central Register of Controlled Trials (1976-2006) were searched for relevant clinical trials and reviews using the terms benign prostatic byperplasia, lower urinary tract symptoms, LUTS, alpha-adrenergic-receptor antagonists, alpha-blockers, 5 alpha-reductase inhibitors, combination therapy, MTOPS, SMART, PREDICT, adverse events, alfuzosin, doxazosin, tamsulosin, terazosin, dutasteride, and finasteride. Abstracts from selected professional conferences also were reviewed. RESULTS: Three previous trials of alpha(1)ARA/5ARI therapy found no therapeutic benefit for combination therapy relative to monotherapy, but their conclusions were limited to some extent by their designs, particularly the duration of treatment. Data from the Medical Therapy of Prostatic Symptoms (MTOPS) study, however, indicated a potential role for long-term use of alpha(1)ARA/5ARI therapy, particularly in patients with greater symptom severity (mean score of 17 on the American Urological Association symptom index), larger prostate volume (mean, 32 g), and higher prostate-specific antigen (PSA) levels (>1.5 ng/mL) at baseline. In the MTOPS study, combination therapy with the alpha(1)ARA doxazosin and the SARI finasteride was significantly more effective than either component alone in reducing BPH-related symptoms (P=0.006 vs doxazosin monotherapy; P<0.001 vs finasteride monotherapy) and lowering the rate of overall clinical progression (P<0.001 vs either monotherapy). In addition, there are data from a subgroup analysis of MTOPS suggesting that the presence of prostatic inflammation may indicate a greater likelihood of treatment efficacy with combination alpha(1)ARA/5ARI therapy. CONCLUSIONS: The available data suggest that combination alpha(1)ARA/5ARI therapy is beneficial in the treatment of BPH and the associated symptoms. The greatest efficacy was evident in patients with an enlarged prostate, more severe symptoms, and higher PSA levels. There are limited data suggesting that the presence of prostatic inflammation may indicate a greater likelihood of treatment efficacy with combination therapy.

Steroid 5alpha-reductase 2 deficiency in two generations of a non-consanguineous Chinese family.

We report a Chinese family in which two family members were diagnosed to have steroid 5alpha-reductase 2 deficiency. The proband was an 8 year-old boy presenting with isolated micropenis. Mutational analysis revealed a homozygous mutation in exon 4 of the SRD5A2 gene, changing codon 227 from CGA to CAA, i.e. R227Q. The paternal granduncle of the proband has incomplete virilization in adulthood. Besides having the mutation R227Q, he has another mutation in exon 5 of the SRD5A2 gene, changing codon 246 from CGG to CAG, i.e. R246Q. To our knowledge, this is the first reported Chinese family diagnosed with steroid 5alpha-reductase 2 deficiency with identified molecular defects.

Medical therapy for benign prostatic hyperplasia: sexual dysfunction and impact on quality of life.

Therapies for benign prostatic hyperplasia (BPH) may either improve or exacerbate sexual function with an ensuing impact on quality of life. Here we review a total of 73 papers on medical therapies for BPH with a focus on the effects of different pharmacological agents on sexual function. For example, certain alpha(1)-adrenergic receptor blockers may improve erectile function; however, ejaculatory dysfunction with one of these agents, tamsulosin, occurs at a rate of 4-18%, rising to 30% with long-term use. In addition, treatment with the 5 alpha-reductase inhibitor finasteride is associated with problems of ejaculation (2.1-7.7%), erection (4.9-15.8%), and libido (3.1-5.4%). Such significant and undesirable complications in relation to sexual function produce a well-documented negative impact on quality of life. Thus, optimal treatment for men with BPH requires the use of agents that demonstrate efficacy and safety with fewer sexual side effects.

Properties and biochemical characterization of NADH 5 alpha-reductase from rat liver microsomes.

NADH 5 alpha-reductase is present in microsomes of various rat organs: heart and skeletal muscle, liver, adrenal glands, kidney, testes and prostate. The enzyme from rat liver microsomes utilizes B-hydrogen from the coenzyme NADH for steroid reduction. After solubilization of the enzyme with the nonionic detergent lubrol, phosphatidylcholine is necessary to restore the activity. This reactivation of the enzyme activity is paralleled by a corresponding increase of Vmax for testosterone (17 beta-hydroxy-4-androsten-3-one). Km and Vmax for testosterone change, Km and Vmax for the coenzyme NADH remain constant with an alteration of phosphate concentration in the incubation medium. The NADH 5 alpha-reductase is inhibited by numerous substances: amytal, phenobarbital, mepacrin, thenoyltrifluoracetone, gallic acid propyl ester, dicoumarol, pentachlorophenol, NADP and antibodies against rat liver NADPH ferrihemoprotein reductase. Antibodies against rat liver cytochrome-b5 reductase cause an activation of NADH 5 alpha-reductase.