Effect of Pygeum africanum tadenan on micturition and prostate growth of the rat secondary to coadministered treatment and post-treatment with dihydrotestosterone

A UPLC- MS/MS Method to Quantify β-Sitosterol and Ferulic Acid of Pygeum Africanum Extract in Bulk and Pharmaceutical Preparation

This study uses a liquid chromatography-electrospray ionization-tandem mass spectrometry method to determine β-Sitosterol and Ferulic acid in Pygeum africanum extract. Chromatographic separation of the two analytes was performed on an ACQUITY UPLC H-Class system coupled with Xevo TQD mass spectrometer and HSS T3 C18 column (2.1 X 50 mm, 1.8 μm). Mobile phase A consisted of an aqueous solution of 0.1% formic acid (v/v), and mobile phase B was 0.1% formic acid (v/v) in methanol pumped through a gradient elution mode. Mass spectrometer parameters were optimized using an electrospray ionization source in the positive and negative ionization modes. The quantification of the two analytes was performed using multiple reaction monitoring transitions. The method was fully validated per (FDA) guidelines regarding linearity, accuracy, precision, carryover and selectivity. The proposed method was applied successfully to determine the two investigated compounds in commercially available pharmaceutical products.

Treatment of Benign Prostatic Hyperplasia by Natural Drugs

Benign prostatic hyperplasia (BPH) is one of the most common urinary diseases affecting men, generally after the age of 50. The prevalence of this multifactorial disease increases with age. With aging, the plasma level of testosterone decreases, as well as the testosterone/estrogen ratio, resulting in increased estrogen activity, which may facilitate the hyperplasia of the prostate cells. Another theory focuses on dihydrotestosterone (DHT) and the activity of the enzyme 5α-reductase, which converts testosterone to DHT. In older men, the activity of this enzyme increases, leading to a decreased testosterone/DHT ratio. DHT may promote prostate cell growth, resulting in hyperplasia. Some medicinal plants and their compounds act by modulating this enzyme, and have the above-mentioned targets. This review focuses on herbal drugs that are most widely used in the treatment of BPH, including pumpkin seed, willow herb, tomato, maritime pine bark, Pygeum africanum bark, rye pollen, saw palmetto fruit, and nettle root, highlighting the latest results of preclinical and clinical studies, as well as safety issues. In addition, the pharmaceutical care and other therapeutic options of BPH, including pharmacotherapy and surgical options, are discussed, summarizing and comparing the advantages and disadvantages of each therapy.

The natural compounds atraric acid and N-butylbenzene-sulfonamide as antagonists of the human androgen receptor and inhibitors of prostate cancer cell growth

Extracts from the plant Pygeum africanum are widely used in the therapy of benign prostate hyperplasia (BPH) and in combinational therapy for prostate cancer, the second leading cause of cancer death and the mostly diagnosed form of cancer in men. The androgen receptor (AR) plays a crucial role in the development of the prostate as well as in prostate diseases. Even though the extracts from P. africanum are considered as beneficial for prostate diseases in clinical trials, and some active compounds for treatment of BPH could be identified, compounds responsible for AR inhibition and the molecular mechanism for inhibition of prostatitis need to be identified. Recently, atraric acid and N-butylbenzene-sulfonamide were isolated from a selective dichlormethane extract of P. africanum as two novel AR antagonistic compounds. The molecular mechanisms of AR inhibition were analyzed and are summarized here. Both compounds are the first known natural, complete and specific AR antagonist.

The natural compound atraric acid is an antagonist of the human androgen receptor inhibiting cellular invasiveness and prostate cancer cell growth

Extracts from Pygeum africanum are used in the treatment of prostatitis, benign prostatic hyperplasia and prostate cancer (Pca), major health problems of men in Western countries. The ligand-activated human androgen receptor (AR) supports the growth of the prostate gland. Inhibition of human AR by androgen ablation therapy and by applying synthetic anti-androgens is therefore the primary goal in treatment of patients. Here, we show that atraric acid (AA) isolated from bark material of Pygeum africanum has anti-androgenic activity, inhibiting the transactivation mediated by the ligand-activated human AR. This androgen antagonistic activity is receptor specific and does not inhibit the closely related glucocorticoid or progesterone receptors. Mechanistically, AA inhibits nuclear transport of AR. Importantly, AA is able to efficiently repress the growth of both the androgen-dependent LNCaP and also the androgen-independent C4-2 Pca cells but not that of PC3 or CV1 cells lacking AR. In line with this, AA inhibits the expression of the endogenous prostate specific antigen gene in both LNCaP und C4-2 cells. Analyses of cell invasion revealed that AA inhibits the invasiveness of LNCaP cells through extracellular matrix. Thus, this study provides a molecular insight for AA as a natural anti-androgenic compound and may serve as a basis for AA derivatives as a new chemical lead structure for novel therapeutic compounds as AR antagonists, that can be used for prophylaxis or treatment of prostatic diseases.

Antiproliferative and apoptotic effects of the herbal agent Pygeum africanum on cultured prostate stromal cells from patients with benign prostatic hyperplasia (BPH)

BACKGROUND

Previous reports show that the herbal agent Pygeum africanum (PA) used to treat benign prostatic hyperplasia (BPH) inhibits proliferation of prostate stromal cells from BPH tissues. To determine underlying mechanisms, we compared proliferative and apoptotic responses to PA between BPH and non-BPH prostate stromal cells with a focus on the specific reaction displayed by stromal cell subsets. An interaction of PA with growth factors and hormones was also investigated.

METHODS

Primary prostate stromal cells from BPH/LUTS patients undergoing open prostatectomy (n = 3) and patients without benign prostatic hyperplasia (BPH) undergoing cystectomy (n = 3) were treated with PA. Cells were characterized by immunofluorescence. Sensitivity to PA was determined using proliferation assays. Apoptosis, transforming growth factor B1 (TGFB1), fibroblast growth factor 2 (FGF2), vimentin, alpha smooth muscle actin (alphaSMA), and smoothelin expression were examined after PA treatment. Cell immunophenotype and proliferation were tested after incubating cells with PA plus either FGF2, TGFB1, vascular endothelial growth factor (VEGF), dihydrotestosterone (DHT) or 17beta-estradiol (E2).

RESULTS

Antiproliferative potency and apoptosis induced by PA on stromal cells were increased in BPH versus non-BPH cells. Apoptosis targeted alphaSMA+ cells, more abundant in BPH cells. Downregulation of TGFB1 expression was induced by PA. FGF2 increased cells sensitivity to PA. Incubation with other mitogenic factors like VEGF, DHT, and E2 decreased sensitivity to PA. Both TGFB1 and E2 blocked the antiproliferative activity of PA.

CONCLUSIONS

Results suggest that PA is antiproliferative and apoptotic on proliferative prostate fibroblasts and myofibroblasts but not on smooth muscle cells. Mechanisms of action include TGFB1 downregulation and inhibition of FGF2 specific signaling.

A critical review of the pharmacology of the plant extract ofPygeum africanumin the treatment of LUTS

Despite an unremitting increase in the number of patients presenting symptoms of benign prostate hyperplasia (BPH), the viable treatment options remain relatively limited when compared to other disorders of aging. This has spurred an interest in so-called alternative medicines, many of which continue to be used in spite of the more recent emergence of rationally targeted therapies. Nonetheless, in the case of plant extracts, the vast majority of these have not been subjected to the same rigorous pre-clinical pharmacological testing and large-scale clinical trials now required by health authorities. Furthermore, demonstration of their clinical efficacy in BPH has been hindered by trials of limited duration with a high placebo response. Beginning with a preliminary demonstration of in vitro inhibition of growth factor-mediated fibroblast proliferation with Pygeum africanum extract, a detailed series of in vitro and in vivo studies on prostate growth and bladder function were undertaken. These studies, reviewed herein, have permitted the identification of putative molecular targets of Pygeum africanum extract affecting both growth factor-mediated prostate growth as well as specific parameters of bladder function. These results, corroborated in part by short-term clinical efficacy, set the stage for a large-scale clinical trial to investigate the efficacy of Pygeum africanum extract in the treatment of lower urinary tract symptoms.

Nonclinical vehicle use in studies by multiple routes in multiple species

The laboratory toxicologist is frequently faced with the challenge of selecting appropriate vehicles or developing utilitarian formulations for use in in vivo nonclinical safety assessment studies. Although there are many vehicles available that may meet physical and chemical requirements for chemical or pharmaceutical formulation, there are wide differences in species and route of administration specific to tolerances to these vehicles. In current practice, these differences are largely approached on a basis of individual experience as there is only scattered literature on individual vehicles and no comprehensive treatment or information source. This approach leads to excessive animal use and unplanned delays in testing and development. To address this need, a consulting firm and three contract research organizations conducted a rigorous data mining operation of control (vehicle) data from studies dating from 1991 to present. The results identified 65 single component vehicles used in 368 studies across multiple species (dog, primate, rat, mouse, rabbit, guinea pig, minipig, chick embryo, and cat) by multiple routes. Reported here are the results of this effort, including maximum tolerated use levels by species, route, and duration of study, with accompanying dose limiting toxicity. Also included are basic chemical information and a review of available literature on each vehicle, as well as guidance on volume limits and pH by route and some basic guidance on nonclinical formulation development.

Pygeum africanum extract inhibits proliferation of human cultured prostatic fibroblasts and myofibroblasts

OBJECTIVE

To investigate the effect of Pygeum africanum (PA) extract on the proliferation of cultured human prostatic myofibroblasts and fibroblasts; this extract is used for treating urinary disorders associated with benign prostatic hyperplasia (BPH).

MATERIALS AND METHODS

Primary cultures of prostatic stromal cells were obtained from histologically confirmed human BPH by enzymatic digestion. Cell proliferation was measured by 5-bromo2'-deoxy-uridine (BrdU) incorporation assays, and cytotoxicity by luminescent quantification of adenylate kinase activity.

RESULTS

Cultured cells were labelled by an anti-vimentin antibody, and most of them by an alpha-smooth-muscle-actin antibody, revealing the presence of fibroblasts and myofibroblasts. BrdU incorporation tests showed that proliferation of cultured human stromal cells, stimulated by fetal calf serum, by basic fibroblast growth factor and by epidermal growth factor, was dose-dependently inhibited by PA extract (5-100 microg/mL). Except at 100 microg/mL, no acute cytotoxicity of the extract was detected after 24 h of culture. Similarly, the extract dose-dependently inhibited the proliferation of Madin-Darby canine kidney epithelial cells, but to a lesser extent; whatever the dose of extract, no acute toxicity was evident on this cell line.

CONCLUSION

PA extract inhibits the proliferation of cultured human prostatic myofibroblasts and fibroblasts. We propose that cultured human prostatic cells offer a reliable model for preclinical screening of therapeutic agents, and to study the mechanisms underlying the inhibition of proliferation.