The role of endoplasmic reticulum stress in the pathophysiology of periodontal disease.

The endoplasmic reticulum (ER) is a principal organelle for folding, post-translational modifications and transport of secretory, luminal, and membrane proteins. ER stress is a condition induced by the accumulation of unfolded or misfolded proteins owing to a variety of physiological and pathological phenomena. To overcome the deleterious effects of ER stress, unfolded protein response (UPR) is initiated to translocate and remove the misfolded and accumulated proteins. Plenty of evidence shows the correlation between ER stress/UPR and the pathology of inflammatory disease. Periodontal disease is a chronic inflammatory disease characterized by the irreversible destruction of periodontal tissues, which associates with the onset and progress of several systemic diseases. Periodontopathic bacterium and pro-inflammatory mediators play a pivotal role in the progress of periodontal disease. Besides, cigarette smoke has long been associated with periodontal disease. As an inflammatory disorder of the periodontium, periodontal disease is highly related to ER stress. In this review, we provide an overview of the pathophysiological effect of ER stress on periodontal disease through five aspects as follow: ER stress and periodontal tissue remodeling, including both soft tissue and hard tissue; ER stress and the inflammation; ER stress and systematic effect during the periodontal disease; last but not least, ER stress and the autophagic apoptosis in cells.

Immunological regulatory effect of flavonoid baicalin on innate immune toll-like receptors.

As an essential component of the innate immune system, Toll-like receptors (TLRs) are a family of well-recognized ligand-binding receptors found in various organisms and initiate host immune responses. Activation of TLRs signaling pathways lead to the induction of numerous genes that function in host defense. Baicalin is a natural compound from the dry raw root of Scutellaria baicalensis (S. baicalensis) and it has been found to exhibit several pharmaceutical actions, such as anti-inflammation, anti-tumor and antivirus. These biological activities are mainly related to the regulatory effect of baicalin on the host immune response. In this review, we provide an overview of the regulation of baicalin on TLRs signaling pathways in various pathological conditions, and highlight potential targets for the development of the regulatory effect of natural compound from traditional Chinese medicine on innate immune system.

The role of autophagy in the pathogenesis of periodontal disease.

Periodontal disease is a chronic inflammatory disease leading to destruction of periodontal tissues. As a local inflammation, periodontopathic bacterium, pro-inflammatory mediators, and local immune response play pivotal role in the progress of periodontal disease. Besides, cigarette smoke has long been associated with periodontal disease and tooth loss. Autophagy is an intracellular degradation process highly conserved from yeast to humans. As a lysosomal degradation pathway of self-digestion, it is critical for maintaining cells homeostasis and development. The role of autophagy has been investigated in oral diseases, such as oral cancer, periapical lesions, and oral candidiasis. Recently, increasing studies investigated the role of autophagy in periodontal disease. In this review, we try to illustrate the effect of autophagy on periodontal disease pathogenesis from 5 aspects: autophagy affects the intracellular infection and survival of bacteria; autophagy has an interaction with periodontal inflammation; autophagy is pivotal in periodontal cells biology and periodontal tissues destruction and reconstruction; autophagy can be induced by cigarette smoke; last but not least, autophagy may affect periodontal disease via endoplasmic reticulum stress.

Dietary supplementation of soy germ phytoestrogens or estradiol improves spatial memory performance and increases gene expression of BDNF, TrkB receptor and synaptic factors in ovariectomized rats.

BACKGROUND: Estrogen or phytoestrogens treatment has been suggested to improve cognitive function of the brain in postmenopausal women. However, there is lack of information on the mechanism of such treatment on the central nervous system. The present study aimed to determine the effects of estradiol and soy germ phytoestrogens on spatial memory performance in ovariectomized rats and to explore the underlying mechanisms affecting the central nervous system. METHODS: Ovariectomized Sprague-Dawley rats were fed a basic diet supplemented with soy germ phytoestrogens (0.4 g/kg or 1.6 g/kg) or 17ß-estradiol (0.15 g/kg) for 12 weeks. At the end of the experiment, animals were evaluated for their spatial learning and memory performance by the Morris Water Maze task. The expressions of brain-derived neurotrophic factor (BDNF) and synaptic formation proteins in the hippocampal tissue were estimated using RT-PCR and ELISA. RESULTS: It was found that rats supplemented with soy germ phytoestrogens or estradiol performed significantly better in spatial memory acquisition and retention when compared to the rats fed on the control diet. Estradiol or the high dose of phytoestrogens treatment significantly increased BDNF concentration and the mRNA levels for BDNF and its TrkB receptors as well as the synaptic formation proteins, synaptophysin, spinophilin, synapsin 1 and PSD-95, in the hippocampal tissue of the experimental animals. It was also found that phytoestrogens, in contrast to estradiol, did not show any significant effect on the vaginal and uteri. CONCLUSION: Soy germ phytoestrogens, which may be a substitute of estradiol, improved spatial memory performance in ovariectomized rats without significant side-effects on the vaginal and uteri. The memory enhancement effect may relate to the increase in BDNF and the synaptic formation proteins expression in the hippocampus of the brain.

[Effect of fructus corni polysaccharides on damaged sexual function of male rats].

OBJECTIVE: To observe the effects of Fructus Corni polysaccharides (FCP) on sexual function of hemicastrated rats. METHOD: 70 male SD rats are randomly divided into 7 groups with their right testis extirpated except for normal control group. Normal control group and negative control group are given saline (ig) while positive control group are injected hypodermically testosterone propionate at dose of 2 mg x kg(-1) x d(-1). FCP control groups are given FCP separately at dose of 10, 50, 100, 150 mg x kg(-1) x d(-1) (ig). Mating test and erective test are observed. The levels of serum sex hormone T, LSH, FSH, E2 are detected with the Radioimmunoassay (RIA). RESULT: Incubation period of penis erection and mounting are shortened in FCP control groups and positive control group, and the percentage of mounting rats is increased. The level of serum sex hormone T is increased, but estradiol level is reduced. The organ coefficient of foreskin gland and seminal vesicle-prostate gland as well as sperm count and vigor are increased significantly (P < 0.01 or P < 0.05). CONCLUSION: FCP can increase the sexual function of hemicastrated rats. The mechanism is probably through adjustment of the hypothalamus-pituitary-gonadal axis.

Lycium barbarum polysaccharides induce apoptosis in human prostate cancer cells and inhibits prostate cancer growth in a xenograft mouse model of human prostate cancer.

Lycium barbarum polysaccharides (LBPs) are important functional constituents in red-colored fruits of L. barbarum (Guo Qi Zi, a well-known traditional Chinese medicinal plant commonly known as Goji berry or wolfberry). The influence of LBP on human prostate cancer cells was systematically investigated in vitro and in vivo. The in vitro effects of LBP on two cell lines (PC-3 and DU-145) were examined by using trypan blue exclusion staining, single-cell gel electrophoresis, flow cytometry, terminal dUTP nick-end labeling assay, and immunohistochemical assay (assessment of Bcl-2 and Bax expression). The in vivo effect of LBP on PC-3 cells was assessed in the nude mouse xenograft tumor model. The in vitro results showed that LBP can dose- and time-dependently inhibit the growth of both PC-3 and DU-145 cells. LBP caused the breakage of DNA strands of PC-3 and DU-145 cells; the tail frequency and tail length were significantly higher than that of control cells. LBP also markedly induced PC-3 and DU-145 cell apoptosis, with the highest apoptosis rates at 41.5% and 35.5%, respectively. The ratio of Bcl-2/Bax protein expression following LBP treatments decreased significantly with a dose-effect relationship, which suggested that LBP can regulate the expression of Bcl-2 and Bax to induce apoptosis of PC-3 and DU-145 cells. The in vivo experimental results indicate that LBP might significantly inhibit PC-3 tumor growth in nude mice. Both the tumor volume and weight of the LBP treatment group were significantly lower than those of the control group.

Lycium barbarum polysaccharides: Protective effects against heat-induced damage of rat testes and H2O2-induced DNA damage in mouse testicular cells and beneficial effect on sexual behavior and reproductive function of hemicastrated rats.

Lycium barbarum, a famous Chinese medicinal herb, has a long history of use as a traditional remedy for male infertility. Polysaccharides are the most important functional constituent in L. barbarum fruits. We systematically investigated the effect of L. barbarum polysaccharides (LBP) on rat testis damage induced by a physical factor (43 degrees C heat exposure), on DNA damage of mouse testicular cells induced by a chemical factor (H2O2), and on sexual behavior and reproductive function of hemicastrated male rats. The results showed that LBP provided a protective effect against the testicular tissue damage induced by heat exposure. When compared with negative control, a suitable concentration of LBP significantly increased testis and epididymis weights, improved superoxide dismutase (SOD) activity, and raised sexual hormone levels in the damaged rat testes. LBP had a dose-dependent protective effect against DNA oxidative damage of mouse testicular cells induced by H2O2. LBP improved the copulatory performance and reproductive function of hemicastrated male rats, such as shortened penis erection latency and mount latency, regulated secretion of sexual hormones and increased hormone levels, raised accessory sexual organ weights, and improved sperm quantity and quality. The present findings support the folk reputation of L. barbarum fruits as an aphrodisiac and fertility-facilitating agent, and provide scientific evidence for a basis for the extensive use of L. barbarum fruits as a traditional remedy for male infertility in China.

[Study on the inhibitory effects of juice of tomato on the growth of human prostate carcinoma PC-3 cells].

OBJECTIVE: To study on the inhibitory effects of juice of tomato on the growth of human prostate carcinoma PC-3 cells and its possible mechanism. METHODS: PC-3 cells were treated with the juice of tomato in different concentration (40, 80, 120 ul/ml) for 48h; the proliferation of PC-3 cells were measured by MTT assay, the comet assay was used to measure the DNA damage of PC-3 cells. RESULTS: Juice of tomato could inhibit the proliferation of PC-3 cells, the growth inhibitory rate of experimental groups were significantly higher than that of control group, with very statistical significance; and it could induce the breakage of DNA single strand of PC-3 cells and resulted in comet cells with tail, Rate of DNA tail and the tail length of DNA increased with the increasing of concentration of juice of tomato, showing the obvious dose effect relationship. CONCLUSION: Juice of tomato could lead to DNA damage of PC-3 cells, it was related to that could inhibit the proliferation of PC-3 cells.