To observe the effect of different concentrations of glutamine (Gln) on the radiosensitivity of colorectal cancer HT-29 cells and explore the possible mechanism.

According to different Gln concentrations, HT-29 cells at logarithmical growth were divided into control group (2 mmol/L, as the basal medium concentration group) and experimental groups Ⅰ, Ⅱ and Ⅲ (4, 6 and 8 mmol/L). After a 2-hour pre-treatment, all groups were exposed to 8 Gy irradiation of a Co-60 radiation source. CCK-8 assay and clonal formation assay were used respectively to explore the effects of different Gln concentrations on cell viability and cell radiosensitivity after irradiation. The level of reactive oxygen species (ROS) in each group was measured in 24 h after irradiation, and the apoptotic rate was detected with flow cytometry in 48 h after irradiation. The protein expression levels of Nrf2, HO-1, and cleaved-Caspase3 were determined by Western blotting.

In 24 h after Gln intervention, the cell viability of experimental groups Ⅱ and Ⅲ of non-irradiated HT-29 cells was significantly higher than that of the control group and of experimental group Ⅰ (P<0.05). In 24 h after radiation, the cell viability of each experimental group was significantly higher than that of the control group (P<0.05). In 14 d after radiation, there were more clone formation in each experimental group than the control group (P<0.05). The ROS level was significantly lower in each experimental group than the control group in 24 h after radiation (P<0.05). After 48 h of radiation, the apoptotic rate was notably lower in each experimental group than the control group (P<0.05). The expression level of Nrf2 in the experimental group Ⅰ was higher than that of the control group (P<0.05), those of Nrf2 and HO-1 in the experimental groups Ⅱ and Ⅲ were higher than those of the control group and experimental group Ⅰ (P<0.05). While the expression of cleaved-Caspase3 in the experimental groups Ⅱ and Ⅲ was lower than the control group and experimental group Ⅰ (P<0.05), and it in the experimental group Ⅲ was lower than that of experimental group Ⅱ (P<0.05).

Gln can significantly reduce the radiosensitivity of HT-29 cells, which is associated with its reducing oxidative stress damage and reducing cell apoptosis. Our results suggest that Gln might be detrimental to radiation therapy in patients with colorectal cancer.

To observe the effect of topical fish oil on wound healing in rats with type 2 diabetes mellitus (T2DM) and to investigate its mechanism of action.

The T2DM rat model was established on 57 SD rats with a high-fat, high-sugar diet combined with intraperitoneal injection of STZ, and finally, T2DM model was established successfully in 49 rats. Then wound model was inflicted surgically, and the rats were divided into fish oil group (n=17), corn oil group (n=16) and model control group (n=16). Topical medication was applied to each group on the next day after wound modelling. During the intervention period, the wound healing was observed in all rats of each group. After the wound tissue samples were collected on 7 and 14 d after wound modelling, the levels of oxidative stress indexes (MDA, SOD and CAT) and inflammatory factors (TNF-α, IL-1β, IL-6 and IL-10) were detected, and pathological changes and collagen fibril deposition in the dermis were observed with HE and Masson staining. The expression of SIRT1, Nrf2 and NQO1 was measured with Western blotting.

Compared with the corn oil group and the model control group, the fish oil group had significantly improved wound healing rate on 7 and 14 d after modelling (P<0.05), increased collagen fibril deposition, decreased levels of MDA, TNF-α, IL-1β and IL-6 in wound tissue (P<0.05), while increased SOD, CAT and IL-10 levels (P<0.05), and protein levels of SIRT1, Nrf2 and NQO1 in the wound tissue (P<0.05). There were no statistical differences in above indicators between the corn oil group and the model control group (P<0.05).

Topical application of fish oil can effectively promote wound healing in T2DM rats, and the mechanism may be related to its reduction of oxidative stress and inflammation of wound.

To explore the effect and underlying mechanism of long-term intake of sodium carboxymethyl cellulose (CMC-Na), a food additive, on radiation tolerance in mice.

Dietary intervention was performed on the mice by adding different concentrations of CMC-Na to drinking water at a dose of 0, 0.25% and 1%, respectively (Control and low-and high-dose groups) for 8 weeks, and then the mice were given a lethal radiation of 7 Gy ⁶⁰Co gamma rays to establish a radiation damage model. Before and after the radiation intervention, the body weight was measured weekly in every mice, and death was observed and recorded in each group. After an 8-week intervention, the blood biochemical indicators of mice were assessed. ELISA, Qrt-Pcr, and Western blotting techniques to investigate changes in intestinal-related cytokines and proteins. What's more, HE staining, immunofluorescence assay and immunohistochemical staining were used to observe the changes of intestinal tissue morphology for pathological scores. Flow cytometry was employed to detect the proportion of intestinal stem cells.

Flow cytometry showed that the proportion of intestinal stem cells was decreased in both dietary intervention groups when compared with the control group (P<0.05), and the decrease was positively correlated with the dose of CMC-Na in drinking water and persisted after radiation damage. Higher death rate (P<0.05) and obvious weight loss (P<0.000 1) were observed in the high-dose intervention group, and impaired intestinal barrier function and a decrease in the content of the anti-inflammatory factor IL-10 were found in further research. Meanwhile, the expression levels of inflammatory factors such as TLR4, NF-κB, TNF-α and IL-1β were higher in the high-dose intervention group (P<0.05), and the contents were further increased after radiation damage. The expression of certain inflammatory factors (NF-κB, TNF-α, and IL-1β) in the low-dose group exhibited a statistically significant increase compared to the control group (P<0.05), yet remained lower than that observed in the high-dose group.

Long-term consumption of foods containing CMC-Na reduces the proportion of colonic stem cells in the intestinal tract, aggravates the radiation damage to the intestine, and reduces the radiation tolerance of mice.

To observe the effect of equol（Eq）intervention on palmitic acid（PA）-induced myoblast atrophy in rat myoblast cell line L6 and to explore its underlying mechanism.

L6 cells were divided into control group, model group（0.25 mmol/L PA）, intervention group（0.25 mmol/L PA+1 μmol/L Eq）and autophagy inhibitor（3-methyladenine, 3-MA）group（0.25 mmol/L PA+1 μmol/L Eq+1 mmol/L 3-MA）. After 24 h of intervention, glucose uptake capacity of cells was detected, muscle tube growth was observed by HE staining, autophagosome number was observed with transmission electron microscopy, and mitochondrial morphology labeled by fluorescent probe was observed by laser confocal microscopy. The expression levels of MyHC, p62, LC3, MFN2 and DRP1 were detected by Western blotting.

Compared with the control group, 24 h of PA treatment resulted in significantly decreased glucose consumption（P<0.05）, decreased muscle tube diameter（P<0.05）, reduced number of autophagosomes, increased mitochondrial fission, and reduced expression levels of MyHC and MFN2（P<0.05）, and elevated DRP1, p62 level and LC3-Ⅰ/LC3-Ⅱ ratio（P<0.05）. While Eq intervention reserved above changes induced by PA treatment（P<0.05）. However, the effects of Eq on PA-induced glucose consumption, myotube diameter, autophagosome number, mitochondrial fission, protein levels of MyHC, p62, MFN2, DRP1 and LC3-Ⅰ/LC3-Ⅱ ratio in L6 cells could be effectively inhibited by 3-MA treatment.

Eq effectively ameliorates PA-induced muscle tube atrophy in L6 cells, which may partially be related to Eq alleviating mitochondrial fission by promoting autophagy.

To observe the effect of equol（Eq）intervention on osteoblasts induced by high glucose and fat, and to explore its mechanism of action.

After ROS1728 osteoblasts were treated with different concentrations of Eq, sodium palmitate（PA）and glucose（GLU）for 48 h, nuclear apoptosis was observed by HE staining and cell survival rate was detected by CCK-8 assay in order to determine the optimal concentrations of GLU, PA and Eq interventions to induce cellular model of diabetic osteoporosis. ROS1728 cells were then divided into control group（5.5 mmol/L GLU）, model group（30 mmol/L GLU+250 μmol/L PA）, and low, medium and high dose Eq treatment groups（model+1×10^-8, 1×10^-7 and 1×10^-6 mol/L Eq）. CCK8 assay was used to detect cell viability, and flow cytometry for cell apoptosis. Hoechst33342 staining and HE staining were employed to observe apoptotic nuclei. Mitochondrial structure, mitochondrial membrane potential（MMP）changes, and protein levels of Sirt1, PGC-1α, Bcl-2, Bax and Cleaved caspase-3 were observed by transmission electron microscopy, Mito-Tracker Red CMXRos（mitochondrial red fluorescent probe）staining, and Western blotting, respectively.

Compared with the control group, treatment of 30 mmol/L GLU and 250 μmol/L PA significantly reduced the cell viability rate（P<0.05）and increased the apoptotic rate（P<0.05）, and the optimal concentrations were determined to induce high glucose and fat environment of osteoblasts. While Eq intervention significantly increased the survival rate and decreased the apoptotic rate（P<0.05）, attenuated the damage of mitochondrial structure, elevated MMP（P<0.05）and decreased ROS level（P<0.05）, as well as up-regulated the expression levels of Sirt1, PGC-1α and Bcl-2 and down-regulated those of Bax and Cleaved caspase-3（P<0.05）.

Eq intervention could effectively reduce mitochondrial damage, oxidative stress and apoptosis of osteoblasts induced by high glucose and fat, which might be partially related to its activation of Sirt1 and PGC-1α.

To investigate the protective effects of aryl hydrocarbon receptor（AhR）activation of 6-formylindolo [3, 2-B] carbazole（FICZ）on intestinal barrier damage and its potential mechanism in a mouse model of total parenteral nutrition（TPN）.

TPN model was established in 18 mice with fluid infusion via external jugular vein, and then the mice randomly divided into control, TPN and TPN+FICZ（1 μg/d）groups. The mice of the TPN group and the TPN+FICZ group were infused with TPN solution and FICZ, those in the control group were treated with same amount of normal saline, and the mice of control group were allowed to eat freely. Their body weight were observed before and in 7 d after catheterization, and peripheral blood sample were harvested to detect intestinal barrier markers. All mice were sacrificed on day 7, and the terminal tissue of ileum was retained to detect protein and RNA expression of relevant molecules and observe the morphological changes of intestinal mucosa.

After 7 d, when compared with the mice of the control group, the mice in the TPN group showed significantly decreased body weight, shorter length of small intestine（P<0.05）, obvious mucosal damages in the intestine, higher Chiu score, increased serum levels of FITC and iFABP（intestinal barrier function indicators）, and enhanced expression levels of TNF-α and IL-1β（P<0.05）, but obviously decreased level of CYP1A1（an indicator of intestinal AhR activation）, and the levels of intestinal barrier tight junction proteins Zo-1 and Occludin and anti-inflammatory factor IL-10 in intestinal tissue（P<0.05）. While, FICZ intervention attenuated above changes in body weight and intestinal length（P<0.05）, improved mucosal damage, reduced Chiu score（P<0.05）, declined serum levels of FITC and iFABP and the levels of TNF-α and IL-1β in intestinal tissue（P<0.05）, and up-regulated the expression levels of CYP1A1, Zo-1, Occludin and IL-10（P<0.05）.

FICZ attenuates TPN-induced intestinal barrier damage in mice through AhR activation to relieve inflammation of intestinal mucosa and regulate expression of tight junction proteins.

To observe the osteoprotective effect of equol（Eq）on postmenopausal rats with nonalcoholic fatty liver disease（NAFLD）, and to explore its underlying mechanism.

Forty-eight 6-week-old female Sprague-Dawley（SD）rats were randomly divided into control group, model group, low-, middle- and high-dose Eq groups [20, 40 and 80 mg/（kg·d）], and estradiol intervention group [E2, 0.25 mg/（kg·d）], with 8 rats in each group. The control group was given sham operation and normal diet. The other groups were given ovariectomy（OVX）combined with high-fat diet. After 16 weeks, the body weight and length of rats were measured, BMI and Lee's index were calculated, and the changes of bone mineral density（BMD）and bone microstructure of rats were detected. After anesthesia, the rats were killed to detect the levels of serum estrogen, TNF-α and IL-6. The liver and femur tissues were observed for morphological changes, and the expression of insulin-like growth factor-1（IGF-1）in the liver and bone was detected by Western blotting and qRT-PCR.

In the model group, BMI and Lee's index were increased significantly, the liver tissue was obviously injured, the estrogen level and BMD were obvioiusly decreased, and the bone microstructure was seriously damaged, suggesting that postmenopausal NAFLD was complicated with obvious bone injury. The treatment of Eq or E2 increased the level of serum estrogen and BMD, decreased BMI, Lee's index and serum TNF-α and IL-6 levels, attenuated steatosis and lipid accumulation in bone microstructure, and enhanced the expression of IGF-1 at protein and mRNA level in the liver and bone.

Eq can improve the bone injury of postmenopausal NAFLD rats and shows a bone protective effect. The mechanism may partially be related to Eq promoting the expression of IGF-1 and reducing inflammation.

To observe the effect of equol（Eq）intervention on sodium oleate（NaOL）-induced steatosis in HepG2 cells and study its mechanism of action.

HepG2 cells were treated with different concentrations of NaOL（0, 0.12, 0.24, 0.36, 0.48, 0.60 and 0.72 mmol/L）for 48 h to induce cell steatosis. Oil red O staining was used to observe the accumulation of intracellular lipid droplets, and triglyceride（TG）content was measured. CCK-8 assay was employed to determine the optimal concentration of NaOL in the inducement of hepatic steatosis and the concentration range for Eq intervention. Then HepG2 cells were randomly divided into 6 groups: control group, NaOL group, NaOL+low-, medium- and high-dose Eq groups（10^-7, 10^-6, and 10^-5 mol/L）, NaOL+estradiol intervention group（E2, 10^-7 mol/L）. After Eq intervention for 48 h, cellular TG content was detected, and Oil red O staining was adopted to observe the accumulation of intracellular lipid droplets, and the expression of SREBP-1c, FAS, PPARα and CPT-1A at mRNA and protein levels was detected by qRT-PCR and Western blotting, respectively.

NaOL of 0.24 mmol/L showed no significant effect on the viability of HepG2 cells, but significantly increased intracellular TG content and accumulated a large number of lipid droplets. Compared with the NaOL group, Eq or E2 intervention reduced the intracellular lipid droplet accumulation in HepG2 cells induced by NaOL, significantly decreased the intracellular TG content（P<0.05）, down-regulated the mRNA and protein expression levels of SREBP-1c and FAS（P<0.05）, and up-regulated those of PPARα and CPT-1A（P<0.05）.

Eq could effectively improve NaOL-induced steatosis in HepG2 cells, and it may be related to its inhibiting SREBP-1c and FAS expression, while enhancing PPARα and CPT-1A expression.

To analyze the effects of S-Equol on glucose and lipid metabolism in rats with type 2 diabetes mellitus (T2DM) and nonalcoholic fatty liver disease (NAFLD).

Fifty SD rats aged 6 weeks were randomly divided into the control group (n=10) and the modeling group (n=40) after 1 week's adaptive feed. The modeling group was given high-fat and high-sugar diet combined with streptozotocin (STZ) intrabdominal injection to construct T2DM model. Rats whose fasting blood-glucose (FBG) level was greater than 11.1 mmol/L were randomly divided into the 4 groups: the model group, the S-Equol low-dose group (20 mg·kg^-1·d^-1), the S-Equol medium-dose group (40 mg·kg^-1·d^-1) and the S-Equol high-dose group (80 mg·kg^-1·d^-1). After 12 weeks of intervention, the level of serum total cholesterol (TC), triglyceride (TG), FBG, high density lipoprotein (HDL), low density lipoprotein (LDL), total bilirubin (TBIL), direct bilirubin (DBIL), total protein (TP), albumin (Alb) and globulin (Glb) were detected. Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and liver interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were detected by ELISA. Peroxisome proliferator-activated receptor gamma (PPARγ), acetyl-CoA carboxylase (ACC), sterol regulatory element binding protein-1 (SREBP-1) and fatty acid synthetase (Fasn) expression levels related to lipid metabolism were detected by Western blotting and RT-qPCR.

Compared with the model group, the S-Equol low-dose group had significantly decreased levels of insulin resistance (P<0.05), the S-Equol medium-dose group had significantly decreased levels of insulin secretion (P<0.05), and the S-Equol low-and high-dose groups had obviously decreased levels of FBG (P<0.05); The S-Equol low-dose group had significantly decreased liver index, albumin/globulin ratio (A/G) and LDL (P<0.05), and the S-Equol medium-dose group had significantly decreased DBIL and ALT (P<0.05). Compared with the model group, the histological morphology of liver in the S-Equol low-, medium- and high-dose groups improved and the area of liver lipid deposition decreased obviously (P<0.05), and the S-Equol medium-dose group and the high-dose group had reduced liver inflammation (P<0.05). The results of Western blotting showed the expression of PPARγ and ACC in liver tissue of rats was significantly down-regulated by medium- and high-dose S-Equol intervention (P<0.05). The results of RT-qPCR showed that S-Equol intervention significantly could reduce the transcription levels of ACC, SREBP-1, Fasn and PPARγ in liver tissue of rats (P<0.05).

The intervention of S-Equol can reduce liver lipid deposition, lipid metabolism-related molecule expression and inflammation in T2DM rats with NAFLD, and the mechanism may be related to regulating SREBP pathway and PPARγ expression.