Recombinant expressed vasoactive intestinal peptide analogue ameliorates TNBS-induced colitis in rats.

AIM: To investigate the modulatory effect of recombinant-expressed vasoactive intestinal peptide (VIP) analogue (rVIPa) on trinitrobenzene sulfonic acid (TNBS)-induced colitis in rats. METHODS: Forty-eight rats were randomized into six groups: normal control group (Control), model control group (TNBS), ethanol treatment group (ETOH), and VIP treatment groups with different dosage (rVIPa1nmol, rVIPa2nmol, rVIPa4nmol). Diarrhea and bloody stool were observed. Colonic damage was evaluated histologically. The levels of tumor necrosis factor-α (TNF-α), interleukin-10 (IL-10), myeloperoxidase (MPO) and endotoxin in colonic tissue and serum were determined by enzyme-linked immunosorbent assay (ELISA). The expression of occludin, ZO-1, Toll-like receptor 4 (TLR4), and nuclear factor-kappa B p65 (NF-κB p65), IκBα, and p-IκBα were detected by Western blot. RESULTS: Administration with 2 nmol rVIPa prevented TNBS-induced necrosis, hyperemia, swelling, inflammation, etc., pathologic changes observed in the inner surface of colon in experimental rats. Moreover, rVIPa significantly decreased colonic TNF-α level (P < 0.001), MPO activity (P < 0.001) and serum endotoxin level (P < 0.01), and remarkably increased colonic IL-10 content (P < 0.001) in rats with TNBS-induced colitis. Furthermore, compared to the TNBS-induced colitis group, 2 nmol rVIPa treatment up-regulated the levels of occludin (P < 0.05) and ZO-1 (P < 0.05), NF-κB p65 (P < 0.01) and IκBα (P < 0.001), and down-regulated the levels of TLR4. CONCLUSION: rVIPa ameliorates TNBS-induced colonic injury and inflammation and effectively protected the intestinal mucosal barrier function in rats. The mechanism may be related to TLR4/NF-κB-mediated signaling pathway. rVIPa could be used as a new alternative therapy for intestinal inflammatory disorders.

Relationship between CaSRs and LPS-injured cardiomyocytes.

OBJECTIVE: Calcium-sensing receptors (CaSRs) regulate systemic calcium homeostasis. Intracellular calcium concentration changes are initiating factors of endoplasmic reticulum stress and cell autophagy. Recent research has revealed that CaSRs play an important role in myocardial ischemia/reperfusion injury and other cardiovascular diseases. However, it remains unclear whether CaSRs are involved in lipopolysaccharide (LPS)-induced cardiomyocyte injury. METHODS: Cultured neonatal rat cardiomyocytes were treated with LPS, with or without pretreatment by a CaSR specific agonist SC-211006 or CaSR specific antagonist SC-207394. The ultrastructure of cardiomyocytes was observed using a transmission electron microscope, and the expression of CaSR, GRP78, LC3B, CytC and Bcl-2 proteins were detected by western blot. RESULTS: Compared with the control group, LPS increased cardiomyocyte injury and the expression of CaSR, GRP78, LC3B and CytC proteins, but decreased the expression of Bcl-2. Compared with the LPS group, pretreatment with SC-211006 further enhanced cardiomyocyte damage and the expression of CaSR, GRP78, LC3B and CytC, but reduced the expression of Bcl-2. Conversely, pretreatment with SC-207394 decreased cardiomyocyte injury and the protein expression of CaSR, GRP78, LC3B and CytC, but increased the expression of Bcl-2. CONCLUSION: Our results suggest that CaSRs are involved in LPS-induced rat cardiomyocyte injury via the activation of endoplasmic reticulum stress and autophagy.

Screening of different sample types associated with sheep and cattle for the presence of nematophagous fungi in China.

A total of 1502 samples, including feces of sheep (793) and cattle (348), pasture soil (118), dung compost (147) and barn soil (96), were examined between October 2012 and August 2014 to discover potential strains of nematophagous fungi for the biological control of livestock-parasitic nematodes. These samples were collected from 87 sites located in 48 counties of 20 provinces (autonomous regions/municipalities) of China. Fungi were identified down to a species level. Four hundred and seventy-seven isolates, which were distributed in 8 genera and 28 taxa, were identified as nematophagous fungi. Nematode-trapping fungi included 17 species and one unidentified species of Arthrobotrys, two of Dactylella, Drechslerella dactyloides, and Duddingtonia flagrans. Five identified species and two unidentified species of endoparasitic fungi were isolated. The predominant species from all regions were Arthrobotrys oligospora, followed by Arthrobotrys musiformis, Arthrobotrys (Monacrosporium) thaumasiun, and Arthrobotrys (Monacrosporium) microscaphoides. Species with adhesive networks were the most frequently isolated. Among the endoparasitic fungi, Podocrella harposporifera (Harposporium anguillulae) was the most common species, followed by Harposporium lilliputanum and Harposporium arcuatum. Based on Shannon diversity index, the diversity levels of nematophagous fungi were relatively higher in samples associated with cattle, barn soil, and subtropical monsoon climate zone. Three species isolated from this study, namely, Duddingtonia flagrans, Arthrobotrys salina (Monacrosporium salinum), and Arthrobotrys oligospora var. sarmatica, are newly recorded in China, and 20 species (including one unidentified species) are newly recorded in sheep and cattle barn soils worldwide.

Isolation, identification, and characterization of the nematophagous fungus Monacrosporium salinum from China.

Nematophagous fungi are considered to have the best potential as biological agents for the control of gastrointestinal nematodes in domestic animals. However, relatively few studies have been conducted with the genus Monacrosporium, especially with strains native to China. In the present study, we isolated and identified nematophagous fungi from fresh sheep feces. A pure fungal strain was molecularly characterized, and its nematophagous activity was evaluated. The morphological plasticity of the isolated strain, as well as its interaction with the nematode targets, was observed by scanning electron microscopy of the infected Trichostrongylus colubriformis L3 and the free-living nematode Caenorhabditis elegans. Three isolated fungal strains from the 30 fresh fecal samples of sheep from Inner Mongolia, China exhibited predatory activity; however, only a single strain was successfully purified (SF 0459). The SF 0459 strain was characterized by morphological analysis of its conidia and sequencing of its ITS1-5.8S rDNA-ITS2 region. This strain was identified to be Monacrosporium salinum (GenBank ID: KP036623). Nematophagous fungus helper bacteria were found at the interaction points between fungi and nematodes. The percentage of live T. colubriformis L3 was reduced by 83.79-88.69% based on the in vitro assay.

Protective effect of glutamine on intestinal injury and bacterial community in rats exposed to hypobaric hypoxia environment.

AIM: To investigate the protective effect of glutamine (Gln) on intestinal injury and the bacterial community in rats exposed to hypobaric hypoxia environment. METHODS: Sprague-Dawley rats were divided into control, hypobaric hypoxia (HH), and hypobaric hypoxia + Gln (5.0 g/kg BW·d) (HG) groups. On the first 3 d, all rats were placed in a normal environment. After the third day, the HH and HG groups were transferred into a hypobaric chamber at a simulated elevation of 7000 m for 5 d. The rats in the HG group were given Gln by gavage daily for 8 d. The rats in the control and HH groups were treated with the same volume of saline. The intestinal morphology, serum levels of malondialdehyde (MDA), superoxide dismutase (SOD), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), interferon-gamma (IFN-γ) and diamino oxidase (DAO) were examined. We also evaluated the expression levels of occludin, toll-like receptor 4 (TLR4), nuclear factor-κB p65 (NF-κB p65) and myeloid differentiation factor 88 (MyD88), and examined the bacterial community in caecal contents. RESULTS: Hypobaric hypoxia induced the enlargement of the heart, liver, lung and kidney, and caused spleen atrophy. Intestinal villi damage was also observed in the HH group. Supplementation with Gln significantly alleviated hypobaric-induced damage to main organs including the intestine, increased serum SOD (1.14 ± 0.03 vs 0.88 ± 0.04, P < 0.05) and MDA (8.35 ± 1.60, P < 0.01) levels and decreased serum IL-6 (1172.13±30.49 vs 1407.05 ± 34.36, P < 0.05), TNF-α (77.46 ± 0.78 vs 123.70 ± 3.03, P < 0.001), IFN-γ (1355.42 ± 72.80 vs 1830.16 ± 42.07, P < 0.01) and DAO (629.30 ± 9.15 vs 524.10 ± 13.34, P < 0.001) levels. Moreover, Gln significantly increased occludin (0.72 ± 0.05 vs 0.09 ± 0.01, P < 0.001), TLR4 (0.15 ± 0.05 vs 0.30 ±0.09, P < 0.05), MyD88 (0.32 ± 0.08 vs 0.71 ± 0.06, P < 0.01), and NF-κB p65 (0.16 ± 0.04 vs 0.44 ± 0.03, P < 0.01) expression levels and improved the intestinal bacterial community. CONCLUSION: Gln treatment protects from intestinal injury and regulates the gut flora imbalance in hypoxia environment. These effects may be related to the TLR4/MyD88/NF-κB signaling pathway.

[Developmental status and prospect of musical electroacupuncture].

Through searching domestic and foreign medical journals in CNKI, Wanfang database, VIP database and Pubmed database from January of 2003 to November of 2013, 39 articles regarding musical electroacupuncture (MEA) were analyzed. The result showed that MEA was clinically used to treat neurological and psychotic disorders; because it was combined with musical therapy and overcame the acupuncture tolerability, and MEA was superior to traditional electroacupuncture. However, problems such as low research efficiency and the mechanism of MEA superiority and the musical specificity not being revealed by research design still exist. In future, large-sample multi-center RCT researches should be performed to clarify MEA clinical efficacy. With modern science and technology and optimized study design, guided by five-element theory of TCM, researches on different musical elements and characteristics of musical pulse current as well as MEA's correlation with meridians and organs should be studied, so as to make a further exploration on MEA mechanisms and broaden the range of its clinical application.

[Development of cell-penetrating peptides as vectors for drug delivery].

Biomacromolecules play an important role in the treatment of many diseases, but as a result of cell membrane serving as the natural barriers, only the small molecular compounds whose molecular weights are smaller than 600 Da can get through cell membrane and enter the cell. In recent years, some short peptides (the length less than 30 amino acids) are found to have the cell-penetrating function, called cell-penetrating peptides (CPPs). They are able to effectively translocate segments of protein, polypeptides, nucleic acid into the cells of many mammal animals with many methods. They have high transduction efficiency and will not lead to cell damage. So, the discovery of CPPs has a very good applicable prospect in such research fields as cell-biology, gene-therapy, drug transduction in vivo, evaluation of clinical medicine and medical immunology. This paper reviews the types and characteristics of CPPs, internalization mechanisms, applications, and their existing problems.