Modulatory effect of Tagetes erecta flowers essential oils via Nrf2/HO-1/NF-κB/p65 axis mediated suppression of N-methyl-N'nitro-N-nitroguanidine (MNNG) induced gastric cancer in rats.

Protective effect of Tagetes erecta flowers essential oils was investigated on oxidative stress, immune response, inflammation, and apoptosis against N-methyl-N'nitro-N-nitroguanidine (MNNG) induced gastric cancer in rats. Essential oil were extracted from Tagetes erecta flowers and analyzed using gas chromatography-mass spectrometry (GC-MS). For observing a protective effect against MNNG induced gastric cancer, we divided rats into 4 groups (group A to D) having 10 rats in each group. Performed various experiments and measured a different parameters to investigate antioxidant activity, immune response, anti-inflammatory and anti-apoptotic activity. The levels of malondialdehyde were markedly increased in the presence of N-methyl-N'nitro-N-nitroguanidine, whereas, the antioxidant activities of superoxide dismutase, and catalase were lowered in the treated rats in contrast with the control. Intervention with TEEO to gastric cancer-induced rats upregulated the redox status and the activity of the immune system to decrease cancer risk. The proinflammatory cytokines (IL-6 and TNF-α) secretions that were induced by MNNG were markedly inhibited by TEEO. Administration of TEEO also significantly reduced terminal deoxynucleotidyl transferase dUTP nick end labeling positive gastric cancer cells, expression of mRNA of caspase-3, and Bax. Whereas, the expression of Bcl-2 was increased. Additionally, downregulation of nuclear factor E2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) and IκBα degradation and the nuclear factor-κB (NF-κB) p65 expression in tissues of the stomach of MNNG-induced-rats were markedly elevated due to TEEO. This suggested possession of TEEO with a protective shield against MNNG induced gastric cancer by the exertion of antioxidative stress, anti-apoptotic response, the anti-inflammatory response through Nrf2/HO-1, and NF-κB signaling pathways.

Aqueous Oldenlandia diffusa extracts inhibits colorectal cancer cells via activating AMP-activated protein kinase signalings.

Here we evaluated the anti-cancer activity of aqueous Oldenlandia diffusa (OD) extracts (ODE) in colorectal cancer (CRC) cells. We showed that ODE exerted potent anti-proliferative, cytotoxic and pro-apoptotic activities against a panel of established CRC lines (HCT-116, DLD-1, HT-29 and Lovo) and primary (patient-derived) human CRC cells. ODE activated AMP-activated protein kinase (AMPK) signaling, which led to subsequent mTORC1 inhibition and Bcl-2/HIF-1α downregulation in CRC cells. In ODE-treated CRC cells, AMPKα1 formed a complex with p53. This might be important for p53 activation and subsequent cancer cell apoptosis. Inhibition of AMPK signaling, though dominant negative (dn) mutation or shRNA/siRNA knockdown of AMPKα1 attenuated ODE-exerted CRC cytotoxicity. In vivo, i.p. administration of ODE inhibited HCT-116 xenograft tumor growth in SCID mice. In addition, AMPK activation, mTORC1 inhibition and p53 activation were observed in ODE-treated HCT-116 xenograft tumors. These results suggest that ODE inhibits CRC cells in vitro and in vivo, possibly via activation of AMPK-dependent signalings.

Mechanism involved in Danshen-induced fluid secretion in salivary glands.

AIM: Danshen's capability to induce salivary fluid secretion and its mechanisms were studied to determine if it could improve xerostomia. METHODS: Submandibular glands were isolated from male Wistar rats under systemic anesthesia with pentobarbital sodium. The artery was cannulated and vascularly perfused at a constant rate. The excretory duct was also cannulated and the secreted saliva was weighed in a cup on an electronic balance. The weight of the accumulated saliva was measured every 3 s and the salivary flow rate was calculated. In addition, the arterio-venous difference in the partial oxygen pressure was measured as an indicator of oxygen consumption. In order to assess the mechanism involved in Danshen-induced fluid secretion, either ouabain (an inhibitor of Na(+)/K(+) ATPase) or bumetanide (an inhibitor of NKCC1) was additionally applied during the Danshen stimulation. In order to examine the involvement of the main membrane receptors, atropine was added to block the M3 muscarinic receptors, or phentolamine was added to block the α1 adrenergic receptors. In order to examine the requirement for extracellular Ca(2+), Danshen was applied during the perfusion with nominal Ca(2+) free solution. RESULTS: Although Danshen induced salivary fluid secretion, 88.7 ± 12.8 µL/g-min, n = 9, (the highest value around 20 min from start of DS perfusion was significantly high vs 32.5 ± 5.3 µL/g-min by carbamylcholine, P = 0.00093 by t-test) in the submandibular glands, the time course of that secretion differed from that induced by carbamylcholine. There was a latency associated with the fluid secretion induced by Danshen, followed by a gradual increase in the secretion to its highest value, which was in turn followed by a slow decline to a near zero level. The application of either ouabain or bumetanide inhibited the fluid secretion by 85% or 93%, and suppressed the oxygen consumption by 49% or 66%, respectively. These results indicated that Danshen activates Na(+)/K(+) ATPase and NKCC1 to maintain Cl(-) release and K(+) release for fluid secretion. Neither atropine or phentolamine inhibited the fluid secretion induced by Danshen (263% ± 63% vs 309% ± 45%, 227% ± 63% vs 309% ± 45%, P = 0.899, 0.626 > 0.05 respectively, by ANOVA). Accordingly, Danshen does not bind with M3 or α1 receptors. These characteristics suggested that the mechanism involved in DS-induced salivary fluid secretion could be different from that induced by carbamylcholine. Carbamylcholine activates the M3 receptor to release inositol trisphosphate (IP3) and quickly releases Ca(2+) from the calcium stores. The elevation of [Ca(2+)]i induces chloride release and quick osmosis, resulting in an onset of fluid secretion. An increase in [Ca(2+)]i is essential for the activation of the luminal Cl(-) and basolateral K(+) channels. The nominal removal of extracellular Ca(2+) totally abolished the fluid secretion induced by Danshen (1.8 ± 0.8 µL/g-min vs 101.9 ± 17.2 µL/g-min, P = 0.00023 < 0.01, by t-test), suggesting the involvement of Ca(2+) in the activation of these channels. Therefore, IP3-store Ca(2+) release signalling may not be involved in the secretion induced by Danshen, but rather, there may be a distinct signalling process. CONCLUSION: The present findings suggest that Danshen can be used in the treatment of xerostomia, to avoid the systemic side effects associated with muscarinic drugs.

Preventive effect of Actinidia valvata Dunn extract on N-methyl-N'-nitro-N-nitrosoguanidine-induced gastrointestinal cancer in rats.

PURPOSE: This study was conducted to assess the preventive effect of Actinidia valvata Dunn (AVD) extract on an animal model of gastrointestinal carcinogenesis on the basis of changes in tumor incidence, cell proliferation, and apoptosis. MATERIALS AND METHODS: Seventy-five male Wistar rats were divided into five different treatment groups with 15 rats in each group. Group I was given normal feed, whereas Groups II to IV were treated with 10% sodium chloride in the first six weeks and 100 ug/mL of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in drinking water for 24 weeks. Group II was then given normal feed, whereas Group III was given AVD extract (0.24 g/kg/day) for 12 weeks. Group IV was given AVD extract from the first week to the 36th week, whereas Group V was treated with AVD extract alone for 36 weeks. All rats were sacrificed at the end of the 36-week experiment and assessed for the presence of gastrointestinal tumors. The occurrence of cancer was evaluated by histology. Bax, Bcl-2, Caspase-3, and cyclinD1 were determined by immunohistochemical staining and Western blotting. RESULTS: The incidences of gastric cancer were 0% in Group I, 73.3% in Group II, 33.3% in Group III, 26.7% in Group IV, and 0% in Group V. Bcl-2 and cyclinD1 expression was decreased in AVD extract treated groups, whereas Bax and Caspase-3 expression was increased. Comparison with group II revealed significant differences (p<0.01). CONCLUSIONS: AVD extract exhibits an obvious preventive effect on gastrointestinal carcinogenesis induced by MNNG in rats through the regulation of cell proliferation and apoptosis.

Changes of free radicals and digestive enzymes in saliva in cases with deficiency in spleen-yin syndrome.

OBJECTIVE: To explore the nature of deficiency in spleen-yin syndrome, which could provide scientific theoretical support and practical guidance for clinical Traditional Chinese Medicine (TCM) syndrome differentiation based on biology, and had a strong clinical significance. METHODS: Serum Cu and Zn were detected by atomic absorption spectrophotometer, serum vitamin E by high performance liquid chromatography, serum vitamin C by 2,4-Dinitrophenylhydrazine Colorimetry, total superoxide dismutase (SOD) and Cu and Zn-SOD by the xanthine oxidase method, and malondialdehyde (MDA) by the 2-thiobarbituric acid method (TBA). Total antioxidant capacity was detected by a colorimetry kit. Amylase Activity was detected by an automatic biochemical analyzer. Lysozyme was detected by lysozyme detection plate, the diameter of bacteriolysis circle was measured and the corresponding content of lysozyme was obtained from a table of standard curve values. RESULTS: No significant difference in total SOD and Cu, Zn-SOD was found between deficiency in spleen-yin group and normal group. However, such factors in deficiency in kidney-yin group were significantly lower than the other groups (P < 0.05). The MDA content in both deficiency in spleen-yin group and deficiency in kidney-yin group were significantly higher than that of normal group (P < 0.05), while the total antioxidant capacity was significantly lower than normal group (P < 0.05). The vitamin E content in deficiency in kidney-yin group was significantly lower than that in the other two groups (P < 0.05). No significant difference in the contents of vitamin C, Cu and Zn were observed in these groups. The Zn/Cu level in deficiency in kidney-yin group and the vitamin E level in deficiency in spleen-yin group decreased, but with no significant difference. Amylase activity in unit time in cases with deficiency in spleen-yin was lower than and had significant differences with that in normal cases, and higher than that in cases with deficiency in kidney-yin. The sectional velocity of saliva and the ratio of lysozyme in normal case group were significantly higher than other two groups, while deficiency in the spleen-yin group was significantly higher than the deficiency in kidney-yin group. CONCLUSION: All the results indicated that the objective pathological mechanism between the deficiency in spleen-yin and deficiency in kidney-yin was different.

Effects of Chinese herbs on salivary fluid secretion by isolated and perfused rat submandibular glands.

AIM: To determine whether Chinese herbs (CHs) relieve xerostomia (dry mouth) by increasing salivary secretion. METHODS: The submandibular glands of Wistar rats were surgically isolated and perfused arterially with buffered salt solution. After control perfusion, recording started 5 min prior to the start of stimulation. After fluid secretion was induced by 0.2 mumol/L carbamylcholine (CCh) in the perfusate for 10 min, Chinese herb (CH) was added in the perfusion for 5 min. CCh was then overloaded at 0.2 mumol/L in the perfusion for 20 min. The volume of salivary fluid secretion was recorded by a computer-controlled balance system. RESULTS: Saliva secretion formed an initial ephemeral peak at 30 s followed by a gradual increase to a sustained level. CH alone induced no or little saliva in all types of CH selected. During perfusion with CH, overloading of CCh promoted fluid secretion in 15 of 20 CHs. This promotion was classified into four patterns, which were eventually related to the categories of CH: Overall sustained phase was continuously raised (Yin-nourishing, fluid production-promoting and heat-clearing agents); The sustained secretion rose to reach a maximum then decreased (Qi-enhancing agent); Sustained secretion rose to reach the highest maximum and was then sustained with a slight decline (swelling-reducing, phlegm-resolving and pus-expelling agents); Stimulation of salivary secretion without any added stimulants. Addition of CCh raised the fluid secretion to reach the highest maximum then sharply decreased to a lower sustained level (blood activating agent). CONCLUSION: The present findings lead to the conclusion that various CHs have different promotional effects directly on the salivary gland.

[Study on the mechanism of traditional Chinese medicines in promoting gastrointestinal peristalsis].

Traditional Chinese medicine has accumulated rich experience in treating dysfunction of gastrointestinal peristalsis. In recent years, a large number of studies have been made on the mechanism and effects of traditional Chinese medicines on the gastrointestinal peristalsis, and the concept of "gastrointestinal promoting Chinese medicine" has been advocated. These traditional Chinese medicines can be divided into three types: promoting the gastrointestinal peristalsis, inhibiting the gastrointestinal peristalsis, and bi-directional modulating. The in vivo and/or in vitro experiments showed that some of the traditional Chinese medicines for activating blood or regulating qi could promote the stomach peristalsis, and the traditional Chinese medicines for moistening intestines to relieve constipation or invigorating spleen to promote digestion could accelerate the intestinal peristalsis. The mechanism lies in the neuroregulation and gut-peptide regulation. Further research on multi-regulation and of multi-target should be done, for the mechanism of the traditional Chinese medicines in regulating the gastrointestinal peristalsis is far more complicated.