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Sinomenine Hydrochloride Can Ameliorate Benign Prostatic Hyperplasia by Lowering the 5α-Reductase 2 Level and Regulating the Balance between the Proliferation and Apoptosis of Cells

Benign prostatic hyperplasia (BPH) is a chronic disease that affects the quality of life of older males. Sinomenine hydrochloride (SIN) is the major bioactive alkaloid isolated from the roots of the traditional Chinese medicinal plant Sinomenium acutum Rehderett Wilson. We wondered if the SIN administration exerted a regulatory effect on BPH and its potential mechanism of action. Mice with testosterone propionate-induced BPH subjected to bilateral orchiectomy were employed for in vivo experiments. A human BPH cell line (BPH-1) was employed for in vitro experiments. SIN administration inhibited the proliferation of BPH-1 cells (p < 0.05) by regulating the expression of androgen-related proteins (steroid 5-alpha reductase 2 (SRD5A2), androgen receptors, prostate-specific antigen), apoptosis-related proteins (B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax)) and proliferation-related proteins (proliferating cell nuclear antigen (PCNA), mammalian target of rapamycin, inducible nitric oxide synthase) in vitro. SIN administration decreased the prostate-gland weight coefficient (p < 0.05) and improved the histological status of mice suffering from BPH. The regulatory effects of SIN administration on SRD5A2, an apoptosis-related protein (Bcl-2), and proliferation-related proteins (PCNA, matrix metalloproteinase-2) were consistent with in vitro data. SIN exerted a therapeutic effect against BPH probably related to lowering the SRD5A2 level and regulating the balance between the proliferation and apoptosis of cells. Our results provide an important theoretical basis for the development of plant medicines for BPH therapy.

The Role of MicroRNA in DNA Damage Response

DNA is essential for the development and function of organisms. A number of factors affect DNA integrity and cause DNA damages, such as ultraviolet light, ionizing radiation and hydrogen peroxide. DNA damages activate a series of intracellular reactions, called DNA damage response, which play a crucial role in the pathogenesis of cancers and other diseases. MiRNA is a type of evolutionarily conserved non-coding RNA and affects the expression of target genes by post-transcriptional regulation. Increasing evidences suggested that the expression of some miRNAs was changed in tumor cases. MiRNAs may participate in DNA damage response and affect genomic stability via influencing the processes of cell cycle, DNA damage repair and apoptosis, thus ultimately impact on tumorigenesis. Therefore, the role of miRNA in DNA damage response is reviewed, to provide a theoretical basis for the mechanism of miRNAs’ effects on DNA damage response and for the research of new therapies for diseases.

Icariin ameliorates metabolic syndrome-induced benign prostatic hyperplasia in rats

Metabolic syndrome (MetS) is an immense health issue that causes serious complications in aging males including BPH. Icariin (ICA) is a flavonol glycoside that exerts a plethora of pharmacological effects. The present investigation tested the potential of ICA to ameliorate benign prostatic hyperplasia (BPH) induced by MetS in rats. Animals were allocated to 5 groups in which the first and second groups were kept on water and regular food pellets. MetS was induced in the third, fourth, and fifth groups by keeping the animals on high fructose and salt diets for twelve consecutive weeks. These groups were given vehicle, ICA (25 mg/kg), and ICA (50 mg/kg), respectively. MetS was confirmed by an increase in rats' weight, accumulation of visceral fat, insulin resistance, and dyslipidemia. This was accompanied by manifestation of BPH including increased prostate weight, prostate index, and histopathological alterations. Treating the animals with both doses of ICA significantly ameliorated the increase in weight and index of the prostate as well as altered prostate histopathology. In addition, ICA significantly decreased cyclin D1 expression, upregulated Bax, and downregulated Bcl2 mRNA expression. ICA prevented lipid peroxidation, reduced glutathione depletion, and catalase exhaustion, which further lowered markers of prostate inflammation such as interleukin-6 and tumor necrosis factor-α. Moreover, ICA prevented the decrease in prostate content of phosphorylated 5'-adenosine monophosphate (AMP)-activated protein kinase (pAMPK). In conclusion, ICA protects against MetS-induced BPH. This is due to its antiproliferative, proapoptotic, antioxidant, and anti-inflammatory activities as well as the activation of AMPK.

Optimized Icariin Cubosomes Exhibit Augmented Cytotoxicity against SKOV-3 Ovarian Cancer Cells

Clinical application of icariin (ICA) is limited, despite its activity against cancer growth, because of the low solubility of ICA in an aqueous environment. Therefore, the present study attempted to develop and optimize ICA-loaded cubosome delivery and to explore its efficacy and possible mechanism of action against ovarian cancer. The optimization of the cubosome formulation was performed using the Box‒Behnken statistical design; during the characterization, the particle sizes were in the range of 73 to 183 nm and the entrapment efficiency was 78.3% to 97.3%. Optimized ICA-loaded cubosomes (ICA-Cubs) exhibited enhanced cytotoxicity and apoptotic potential, compared with ICA-raw, against ovarian cancer cell lines (SKOV-3 and Caov 3). The optimized ICA-Cubs showed a relatively non-cytotoxic effect on normal EA.hy926 endothelial cells. Further analysis of cell cycle arrest suggested a potential role in the pre-G1 and G2/M phases for ICA-Cubs in comparison with ICA-raw. ICA-Cubs increased the generation of reactive oxygen species (ROS) and the overexpression of p53 and caspase-3 in the SKOV-3 cell line. In conclusion, the cubosomal delivery of ICA might provide a prospective approach towards the superior control of ovarian cancer cell growth. Its improved efficacy compared with that of the free drug might be due to the improved solubility and cellular permeability of ICA.

Molecular and cellular basis of the anticancer activity of the prenylated flavonoid icaritin in hepatocellular carcinoma

The prenylated flavonoid icaritin (ICT) is currently undergoing phase 3 clinical trial for the treatment of advanced hepatocellular carcinoma (HCC), based on a solid array of preclinical and clinical data. The antitumor activity originates from the capacity of the drug to modulate several signaling effectors in cancer cells, mainly the estrogen receptor splice variant ERα36, the transcription factors STAT3 and NFκB, and the chemokine receptor CXCR4. Recent studies have implicated additional components, including different microRNAs, the generation of reactive oxygen species and the targeting of sphingosine kinase-1. ICT also engages the RAGE-HMGB1 signaling route and modulates the apoptosis/autophagy crosstalk to promote its anticancer activity. In addition, ICT exerts profound changes on the tumor microenvironment to favor an immune-response. Collectively, these multiple biochemical and cellular characteristics confer to ICT a robust activity profile which can be exploited to treat HCC, as well as other cancers, including glioblastoma and onco-hematological diseases such as chronic myeloid leukemia. This review provides an update of the pharmacological properties of ICT and its metabolic characteristics. It also addresses the design of derivatives, including both natural products and synthetic molecules, such as SNG1153 also in clinical trial. The prenylated flavonoid ICT deserves attention as a multifunctional natural product potentially useful to improve the treatment of advanced hepatocellular carcinoma.