TRAF1 meditates lipopolysaccharide-induced acute lung injury by up regulating JNK activation.

Acute lung injury (ALI) is served as a severe life-threatening disease. However, the pathogenesis that contributes to ALI has not been fully understood. Tumor necrosis factor receptor-associated factor 1 (TRAF1) interacts with multiple regulators, performing its diverse role in biological functions. However, the effects of TRAF1 on ALI remain unknown. In this study, we attempted to explore the role of TRAF1 in ALI progression. The findings suggested that TRAF1-knockout (KO) markedly attenuated LPS-induced severe mortality rate in murine animals. LPS-elicited histological alterations in pulmonary tissues were significantly alleviated by TRAF1-deletion. Additionally, TRAF1 knockout effectively attenuated lung injury, as evidenced by the reduced lung wet/dry (W/D) weight ratio, as well as decreased bronchoalveolar lavage fluid (BALF) protein levels and neutrophil infiltration. Meanwhile, TRAF1 deletion markedly lessened inflammation, oxidative stress and apoptosis in BALF and/or lung tissues. The levels of pro-inflammatory cytokines stimulated by LPS were down-regulated by TRAF1 ablation, along with the inactivation of nuclear factor κB (NF-κB). LPS-promoted reactive oxygen species (ROS) generation was decreased in TRAF1-KO mice, partly through the improvement of anti-oxidants. Apoptosis was also inhibited by TRAF1 deletion in lung tissues of LPS-challenged mice through the suppression of cleaved Caspase-3. Moreover, TRAF1 knockout significantly decreased c-Jun N-terminal kinase (JNK) activation and its down-streaming signal of c-Jun in pulmonary samples of LPS-induced mice. Importantly, the in vitro study suggested that promoting JNK activation markedly abrogated TRAF1 knockdown-attenuated inflammation, ROS production and apoptosis in LPS-exposed A549 cells. Therefore, our experimental results provided evidence that TRAF1 suppression effectively protected LPS-induced ALI against inflammation, oxidative stress and apoptosis through the suppression of JNK activity.

Dihydroartemisinin enhances antitumor effect of 5-fluorouracil against gastric cancer by down-regulating SIRT1 expression / 中国病理生理杂志

AIM:To investigate the effect of dihydroartemisinin ( DHA) adjuvant treatment on enhancing the antitumor effect of 5-fluorouracil (5-FU) against gastric cancer .METHODS:The gastric cancer BGC-823 cells were di-vided into control group , DHA group, 5-FU group, 5-FU+DHA group and 5-FU+DHA+SIRT1 plasmid group.The via-bility of BGC-823 cells treated with DHA and 5-FU was measured by MTT assay .The expression of SIRT1 and NADPH ox-idase, activation of caspase-9 and caspase-3, and phosphorylation of ASK1 and JNK in the BGC-823 cells treated with DHA and 5-FU were determined by Western blot .The production of ROS and the apoptosis of the BGC-823 cells treated with DHA and 5-FU were analyzed by flow cytometry .RESULTS:Dihydroartemisinin significantly inhibited the expression of SIRT1 and increased NADPH oxidase protein level (P<0.05).DHA increased the sensitivity of BGC-823 cells to 5-FU, thus decreasing the IC50 of 5-FU to the gastric cancer cells.However, transfection with SIRT1 plasmid decreased the cytotoxicity of DHA and 5-FU co-treatment to the BGC-823 cells.DHA promoted the production of ROS and phosphoryla-tion of ASK1 and JNK induced by 5-FU in the BGC-823 cells ( P<0.05 ) .However , ROS scavenger N-acetylcysteine ( NAC) or JNK specific inhibitor SP600125 inhibited the cell death and activation of caspase-9 and caspase-3 induced by DHA and 5-FU co-treatment (P<0.05).In addition, NAC significantly inhibited the phosphorylation of JNK in the BGC-823 cells co-treated with DHA and 5-FU.However, treatment with SP600125 did not influence the ROS production in the BGC-823 cells, indicating that JNK was the downstream target of ROS pathway .CONCLUSION: Combination of DHA with 5-FU induces caspase-dependent apoptosis in gastric cancer cells through the SIRT 1/NADPH oxidase/ROS/JNK sig-naling pathway .

Effect of electroacupuncture on the rat model of type 2 diabetes mellitus combined with renal hypertension / 中国实验动物学报

Objective To observe the therapeutic effect of acupuncture therapy for the rat model of type 2 diabetes mellitus (T2DM) combined with renal hypertension and try to explore its mechanism. Methods We randomly select 10 Wistar rats as the blank group and 40 rats were used to make the model groups, which were divided into simple diabetes group, simple renal hypertension group, the compound group with electroacupuncture and the compound group without elec?troacupuncture, with 10 rats in each group. After a high fat and sugar diet for 4 weeks, the Wistar rats were given strepto?zotocin i. p. injection to establish models of type 2 diabetes mellitus. Renal hypertension was developed by the“2K1C” im?proved method to make unilateral renal artery ligation?induced renal artery stenosis. Then, electroacupuncture treatment was performed on the rats for 2 weeks except the compound group without electroacupuncture. The changes of values of BP, FBG, Cr, BUN, glycated hemoglobin, renin and Ang II were recorded and analyzed. Results The values of BP, FBG, Cr, BUN, glycated hemoglobin, renin and Ang II in the compound group with electroacupuncture showed a significant re?duction compared with the compound group without electroacupuncture after 2 weeks (P0?05). Conclusions The blood glucose and blood pressure in the rat model of compound group can be reduced to a normal level with continuous electroacupuncture at bilateral acupoints Zusanli, and it can also be kept at a stable level after single electroacupuncture for 2-3 days. The acupuncture therapy is more suitable for early clinical treatment and can be used in basic research with advantages of economic, safe, no side effect and so on.

Tetrapleura tetraptera spice attenuates high-carbohydrate, high-fat diet-induced obese and type 2 diabetic rats with metabolic syndrome features.

BACKGROUND: Tetrapleura tetraptera, a seasoning and nutritive spice is also used in western African folk medicine in the management of wide variety of diseases including diabetes, inflammation and hypertension. Flavonoids and saponins are some abundant secondary metabolic constituents in the fruits of this plant. This study aimed at evaluating the potential therapeutic action of the polyphenol-rich hydroethanolic extract (HET) of this fruit in experimentally induced obese and type 2 diabetic rats (T2DM) with characteristic metabolic syndrome (MetS). METHODS: MetS was induced in rats by high-carbohydrate, high-fat diet and administration of low-dose streptozotocin. Then different oral doses of HET (200 and 400 mg/kg) were administered to T2DM rats for 28 days. A standard antidiabetic drug, metformin (300 mg/kg), was used for comparison. The body weight, systolic blood pressure, oxidative stress and metabolic parameters were then assessed to evaluate the effect of HET on MetS. RESULTS: HET reduced weight gain, fasting blood glucose and plasma insulin levels as well as homeostasis model assessment of insulin resistance (HOMA-IR) and alleviated obesity and T2DM associated oxidative stress and hypertension in rats. Moreover, a significantly hypolipidemic property and an attenuation of liver injury and tissue steatosis was observed after HET administration. HET further demonstrated its anti-inflammation effect via down regulation of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), C-reactive protein (CRP), leptin and an increase in adiponectin. The HET exhibited dose-dependent effects which were comparable to that of metformin. CONCLUSIONS: The present study thereby demonstrates the anti-insulin resistance, antilipidemic, anti-obesity, hypotensive and anti-inflammatory properties of HET; hence it has the potential to be further developed for the management of MetS such as obesity, T2DM and hypertension.

Enhancement of mechanical and thermal properties of oil palm empty fruit bunch fiber poly(butylene adipate-co-terephtalate) biocomposites by matrix esterification using succinic anhydride.

In this work, the oil palm empty fruit bunch (EFB) fiber was used as a source of lignocellulosic filler to fabricate a novel type of cost effective biodegradable composite, based on the aliphatic aromatic co-polyester poly(butylene adipate-co-terephtalate) PBAT (Ecoflex™), as a fully biodegradable thermoplastic polymer matrix. The aim of this research was to improve the new biocomposites' performance by chemical modification using succinic anhydride (SAH) as a coupling agent in the presence and absence of dicumyl peroxide (DCP) and benzoyl peroxide (BPO) as initiators. For the composite preparation, several blends were prepared with varying ratios of filler and matrix using the melt blending technique. The composites were prepared at various fiber contents of 10, 20, 30, 40 and 50 (wt %) and characterized. The effects of fiber loading and coupling agent loading on the thermal properties of biodegradable polymer composites were evaluated using thermal gravimetric analysis (TGA). Scanning Electron Microscopy (SEM) was used for morphological studies. The chemical structure of the new biocomposites was also analyzed using the Fourier Transform Infrared (FTIR) spectroscopy technique. The PBAT biocomposite reinforced with 40 (wt %) of EFB fiber showed the best mechanical properties compared to the other PBAT/EFB fiber biocomposites. Biocomposite treatment with 4 (wt %) succinic anhydride (SAH) and 1 (wt %) dicumyl peroxide (DCP) improved both tensile and flexural strength as well as tensile and flexural modulus. The FTIR analyses proved the mechanical test results by presenting the evidence of successful esterification using SAH/DCP in the biocomposites' spectra. The SEM micrograph of the tensile fractured surfaces showed the improvement of fiber-matrix adhesion after using SAH. The TGA results showed that chemical modification using SAH/DCP improved the thermal stability of the PBAT/EFB biocomposite.

Effect of fluoride on expression of CaN mRNA and protein in bone tissue of rats / 中华病理学杂志

<p><b>OBJECTIVE</b>To investigate the changes of mRNA and protein expression of CaN in the bone of rats with chronic fluorosis, and the mechanism of skeletal fluorosis.</p><p><b>METHODS</b>Thirty-six SD rats were divided into three groups (12 in each group, half male and half female selected according to body weight): control, low-dose and high-dose fluorosis groups. Controls were fed tap water (NaF < 0.5 mg/L), experimental animals in the low- or high-dose groups were fed water containing NaF of 5.0 and 50.0 mg/L, respectively. The rats were sacrificed after 6 months of treatment with fluoride. The serum was kept for testing bone metabolic marker bone gla protein (BGP) by enzyme-linked immunosorbent assay (ELISA), the protein and mRNA levels of CaN in distal femur of the rats with chronic flurosis were assessed by immunohistochemistry and in-situ hybridization.</p><p><b>RESULTS</b>The levels of BGP (1.99 ± 0.62, 2.38 ± 0.16)µg/L in the low- or high-dose fluorosis groups were higher than that in the control group (0.15 ± 0.03) µg/L; and the high fluorosis group showed higher level than the low fluorosis group (all P < 0.05). Compared to the control group (131.11 ± 1.95, 111.82 ± 2.39), the protein and mRNA levels of CaN were higher in the low- or high-dose fluorosis groups (142.69 ± 1.17, 157.54 ± 1.88 and 121.28 ± 3.27, 134.63 ± 3.19, respectively), and the high fluorosis group showed higher levels than the low fluorosis group (all P < 0.05).</p><p><b>CONCLUSIONS</b>BGP content could be used as a bone metabolic index in endemic fluorosis disease. Fluoride might up-regulate the mRNA and protein expression of CaN, and the changes in CaN level may be involved in the increase of the bone turnover and could be one of the pathogenetic factors in fluorosis.</p>