Abstract. Ursolic acid (UA), a natural pentacyclic triterpenoid compound, has been demonstrated to induce apoptosis in various tumors. The aim of the present study was to elucidate the molecular mechanisms of UA-induced apoptosis in HeLa cells. Here, we reported that UA induced apoptosis through the mitochondrial intrinsic pathway in HeLa cells, as shown by release of cytosol cytochrome c, activation of caspase-9 and -3, reduction of Bcl-2 and Bcl-xL, and increase of Bax and Bak. UA down-regulated the phosphorylation of ERK1/2 and p38, whereas phosphorylation of JNK was unchanged. The roles of ERK1/2 and p38 were further confirmed using the ERK1/2 inhibitor (U0126) and p38 inhibitor (SB203580). U0126 markedly increased UA-induced the Bax/Bcl-2 ratio, the increase of cytosol cytochrome c, and the levels of cleaved caspase-3, but SB203580 had little effects on the above characters, suggesting the ERK1/2 signaling pathway is required for apoptosis. Furthermore, UA up-regulated DUSP 1, 2, 4, 5, 6, 7, 9, and 10 mRNA expressions, which may be a clue for the role of dephosphorylation of ERK1/2 and p38. These data suggested that the apoptotic mechanism of UA treatment in HeLa cells was through the mitochondrial intrinsic pathway and closely associated with the suppression of the ERK1/2 signaling pathway.

Aim: Chickpea (Cicer arietinum L) is a traditional Uighur herb. In this study we investigated the estrogenic activities of the isoflavones extracted from chickpea sprouts (ICS) in ovariectomized rats. Methods: Ten-week-old virgin Sprague-Dawley female rats were ovariectomized (OVX). The rats were administered via intragastric gavage 3 different doses of ICS (20, 50, or 100 mg·kg -1 ·d -1 ) for 5 weeks. Their uterine weight and serum levels of 17β-estradiol (E 2 ), follicle stimulating hormone (FSH) and luteinizing hormone (LH) were measured. The epithelial height, number of glands in the uterus, and number of osteoclasts in the femur were histologically quantified, and the expression of proliferating cell nuclear antigen (PCNA) was assessed immunohistochemically. Bone structural parameters, including bone mineral density (BMD), bone volume/tissue volume (BV/TV), trabecular thickness (Tb.Th) and trabecular separation (Tb.Sp) were measured using Micro-CT scanning. Results: Treatments of OVX rats with ICS (50 or 100 mg·kg -1 ·d -1 ) produced significant estrogenic effects on the uteruses, including the increases in uterine weight, epithelial height and gland number, as well as in the expression of the cell proliferation marker PCNA. The treatments changed the secretory profile of ovarian hormones and pituitary gonadotropins: serum E 2 level was significantly increased, while serum LH and FSH levels were decreased compared with the vehicle-treated OVX rats. Furthermore, the treatments significantly attenuated the bone loss, increased BMD, BV/TV and Tb.Th and decreased Tb.Sp and the number of osteoclasts. Treatment of OVX rats with the positive control drug E 2 (0.25 mg·kg -1 ·d -1 ) produced similar, but more prominent effects.Conclusion: ICS exhibits moderate estrogenic activities as compared to E 2 in ovariectomized rats, suggesting the potential use of ICS for the treatment of menopausal symptoms and osteoporosis caused by estrogen deficiency.

Dithiocarbamates (DTCs) exhibit a broad spectrum of antitumor activities, however, their molecular mechanisms of antitumor have not yet been elucidated. Previously, we have synthesized a series of novel dithiocarbamate derivatives. These DTCs were examined for cytotoxic activities against five human cancer cell lines. In this study, one of dithiocarbamate (DTC1) with higher potential for HeLa cells was chosen to investigate molecular mechanisms for its anti-tumor activities. DTC1 could inhibit proliferation, and highly induce apoptosis in HeLa cells by activating caspase-3, -6 and -9; moreover, activities of caspase-3, -6 and -9 were inhibited by pan-caspase inhibitor, Z-VAD-FMK. Furthermore, DTC1 decreased the levels of Bcl-2 and Bcl-xL, and increased expression of cytosol cytochrome c, Bak, Bax and p53 in a time-dependent manner but had no effect on the level of Rb. It was shown that DTC1 induced HeLa cells apoptosis through a p53-dependent pathway as tested by the wild type p53 inhibitor, pifithrin-α. Additionally, the relative expression of E6 and E7 were evaluated in HPV18-positive (HeLa cells) by real-time PCR and western blotting. The results firstly demonstrated that DTC1 suppressed both expression of E6 mRNA and E6 oncoprotein, but had no effect on the expression of E7 mRNA and protein in HPV18. Our results suggested that DTC1 may serve as novel chemotherapeutic agents in the treatment of cervical cancer and potential anti-HPV virus candidates that merit further studies.