Investigation of cancer-associated fibroblasts and p62 expression in oral cancer before and after chemotherapy.

PURPOSE: The aim of this study is to investigate the expression of the autophagy protein p62 in oral squamous cell carcinoma (OSCC) cells before and after chemotherapy. We also detected cancer-associated fibroblasts (CAFs) in these OSCC samples to explore the roles of p62 and CAFs in chemotherapy. MATERIALS AND METHODS: Immunohistochemistry was used to analyze the expression of p62 and α-SMA in 26 paired OSCC samples before and after chemotherapy. The relationships between clinicopathological features, clinical outcome and the expression of these proteins were analyzed. RESULTS: Our results indicated an increased stromal α-SMA expression after chemotherapy in OSCC samples. High p62 expression of OSCC cells closely correlated with stromal α-SMA expression after chemotherapy. Furthermore, the post-chemotherapy p62 expression was associated with the prognosis for OSCC patients. CONCLUSION: These results suggest that chemotherapy may increase CAFs in OSCC. High cytoplasmic p62 expression may serve as a poor prognostic marker for OSCC patients.

Soyasaponins prevent H2O2-induced inhibition of gap junctional intercellular communication by scavenging reactive oxygen species in rat liver cells.

It appears to be more practical and effective to prevent carcinogenesis by targeting the tumor promotion stage. Gap junctional intercellular communication (GJIC) is strongly involved in carcinogenesis, especially the tumor promotion stage. Considerable interest has been focused on the chemoprevention activities of soyasaponin (SS), which are major phytochemicals found in soybeans and soy products. However, less is known about the preventive effects of SS (especially SS with different chemical structures) against tumor promoter-induced inhibition of GJIC. We investigated the protective effects of SS-A1, SS-A2, and SS-I against hydrogen peroxide (H2O2)-induced GJIC inhibition and reactive oxygen species (ROS) production in Buffalo rat liver (BRL) cells. The present results clearly show for the first time that SS-A1, SS-A2, and SS-I prevent the H2O2-induced GJIC inhibition by scavenging ROS in BRL cells in a dose-dependent manner at the concentration range of from 25 to 100 µg/mL. Soyasaponins attenuated the H2O2-induced ROS through potentiating the activities of superoxide dismutase and glutathione peroxidase. This may be an important mechanism by which SS protects against tumor promotion. In addition, various chemical structures of SS appear to exhibit different protective abilities against GJIC inhibition. This may partly attribute to their differences in ROS-scavenging activities.

Brazilian green propolis improves immune function in aged mice.

Aging weakened innate and adaptive immunity both quantitatively and qualitatively. Some components in propolis could stimulate immune function in young animals or cultured immune cells in vitro. Few studies had been carried out in the aged. The present study was to evaluate the effects of Brazilian green propolis supplementation on the immunological parameters in aged mice. Eighty Kunming mice, aged 15-18 months, were randomly assigned to the control and three experimental groups supplemented with different doses (83.3, 157.4 and 352.9 mg/kg.bw respectively) of Brazilian green propolis. The experiment lasted for 4 weeks. Contents of total polyphenol, flavonoid, cinnamic acid and artepillin-C in Brazilian green propolis were analyzed. Splenic NK cytotoxic, T lymphocyte proliferation and antibody generation cells, as well as the phagocytosis of peritoneal macrophages, ear swelling, and serum contents of IgG, IgM, hemolysin and cytokines were measured. After 4 weeks of treatment, the phagocytosis of peritoneal macrophages was enhanced in 157.4 mg/kg and 352.9 mg/kg groups. Ear swelling increased in all propolis treatmented groups. Antibodies specific to sheep erythrocytes were higher in the groups receiving 157.4 and 352.9 mg/kg.bw than that of control group. IgG level dramatically increased in the groups receiving 83.3 and 157.4 mg/kg.bw in comparison to the control group. These results indicate that administration of Brazilian green propolis have a positive effect on innate and adaptive immunity in aged mice.

Anti-inflammatory effect of soyasaponins through suppressing nitric oxide production in LPS-stimulated RAW 264.7 cells by attenuation of NF-κB-mediated nitric oxide synthase expression.

The anti-inflammatory properties of soyasaponins (especially soyasaponins with different chemical structures) have scarcely been investigated. We investigated the inhibitory effects of five structural types of soyasaponins (soyasaponin A(1), A(2), I and soyasapogenol A, B) on the induction of nitric oxide (NO) and inducible NO synthase (iNOS) in murine RAW 264.7 cells activated with lipopolysaccharide (LPS). Soyasaponin A(1), A(2) and I (25-200 µg/mL) dose-dependently inhibited the production of NO and tumor necrosis factor α (TNF-α) in LPS-activated macrophages, whereas soyasapogenol A and B did not. Furthermore, soyasaponin A(1), A(2) and I suppressed the iNOS enzyme activity and down-regulated the iNOS mRNA expression both in a dose-dependent manner. The reporter gene assay revealed that soyasaponin A(1), A(2) and I decreased LPS-induced nuclear factor kappa B (NF-κB) activity. Soyasaponin A(1), A(2) and I exhibit anti-inflammatory properties by suppressing NO production in LPS-stimulated RAW 264.7 cells through attenuation of NF-κB-mediated iNOS expression. It is proposed that the sugar chains present in the structures of soyasaponins are important for their anti-inflammatory activities. These results have important implication for using selected soyasaponins towards the development of effective chemopreventive and anti-inflammatory agents.

[Establishment and assessment of Caco-2 cell in vitro absorption model].

OBJECTIVE: To establish and assess the Caco-2 cell in vitro absorption model. METHODS: Caco-2 cells were cultured on the millipore filters fixed in Snapwell transport chamber. The cell morphology, transepithelial electrical resistance, mannitol efflux rate and alkaline phosphatase activities were monitored during culture. RESULTS: After 21 days of in vitro culture, formation of tight junction was observed between the cells. The transepithelial electrical resistance reach a relatively stable value of 620-/+47 Omega.cm(2), the mannitol efflux rate was lower than 0.3%.h(-1).cm(-2), and the alkaline phosphatase activity in the apical side was significantly higher than that in the basolateral side. CONCLUSION: The established Caco-2 cell model shows similar morphology to intestinal epithelial cells with formation of polarity, and can be used as an in vitro model for absorption studies.

Chromium(III) nanoparticles affect hormone and immune responses in heat-stressed rats.

This study was conducted to evaluate the effects of chromium nanoparticles (CrNano) on the hormone and immune responses of rats in heat stress condition. A total of 80 male Sprague-Dawley rats were randomly assigned to four dietary treatment groups (n = 20). The first group was offered a basal diet as a control. The second, third, and fourth groups received basal diet supplemented with 150, 300, and 450 microg/kg Cr, respectively, in the form of CrNano. At the end of the 8-week trial, growth performance, food utilization, and sera concentrations of hormones, immunoglobulins, and alexins were determined. Lymphocyte proliferation activity, antibody response to injected sheep red blood cells (SRBCs), and phagocytosis of peritoneal macrophages were determined by (3)H-thymidine uptake method, plaque-forming cells (PFC) assay, and ingesting chicken red blood cells test, respectively. The results indicated that rats that received CrNano exhibited no changes in growth rate and food efficiency compared to the control group. However, dietary supplementation of 150, 300, and 450 microg/kg Cr from CrNano significantly decreased serum concentrations of insulin and cortisol, increased sera levels of insulin-like growth factor I and immunoglobulin G, and enhanced the lymphoproliferative response, anti-SRBC PFC response, and phagocytic activity of peritoneal macrophages. These results suggest that dietary supplementation of Cr as CrNano affects hormone and immune status in heat-stressed rats.

[Differentiation of neonatal rat striatal neural stem cells induced by all-trans retinoic acid].

OBJECTIVE: To investigate the role of all-trans retinoic acid (atRA) in inducing differentiation of neonatal rat striatal neural stem cells (NSCs). METHODS: Neonatal rat striatal NSCs were obtained by mechanical isolation and serum-free culture. The roles of atRA at different concentrations in inducing the differentiation of NSCs were observed by immunofluorescent cytochemical staining, and the expression of retinoic acid receptor (RAR) gene was determined by semi-quantitative RT-PCR. RESULTS: atRA could dose-dependently accelerate the differentiation of NSCs into neuron-like cells, and the physiological concentration of atRA was optimal for inducing NSC differentiation. atRA could induce the expression of RARbeta mRNA in a dose- and time-dependent manner. CONCLUSION: atRA can accelerate differentiation of NSCs into neuron-likes cells and up-regulate the expression of RAR-beta mRNA in neonatal rat striatal NSCs.