Aldgamycins J-O, 16-Membered Macrolides with a Branched Octose Unit from Streptomycetes sp. and Their Antibacterial Activities

Six new 16-membered macrolides with a rare branched octose unit, aldgamycins J-O (1-6), along with two known compounds, swalpamycin B (7) and chalcomycin (8), were isolated from Streptomyces sp. HK-2006-1. Their structures were determined by detailed spectroscopic and X-ray crystallographic analysis. Natural products containing branched sugar units are rare. Aldgaropyranose and decarboxylated aldgaropyranose are branched octoses, specifically aldgarose-type branched octose. Until now, only 11 compounds have been reported to contain an aldgarose-type branched octose. The discovery of aldgamycins J-O (1-6) adds new members of this type of natural product. All the compounds (1-8) herein were tested for antimicrobial activities against Gram-positive Staphylococcus aureus 209P, Gram-negative Escherichia coli ATCC0111, and two fungi, Candida albicans FIM709 and Aspergillus niger R330. Most of these compounds showed antibacterial activity against S. aureus. Their preliminary structure-activity relationships are proposed.

[Association of Crohn's disease with transcobalamin Ⅱ gene polymorphisms and serum homocysteine, folate and vitamin B12 levels in Chinese patients]

OBJECTIVE

To investigate the association of Crohn's disease (CD) with transcobalamin Ⅱ (TCN2) gene polymorphisms and serum homocysteine (Hcy), folate, and vitamin B12 levels in Chinese patients.

METHODS

In a total of 307 CD patients (CD group) and 574 healthy controls (control group) of Han ethnicity selected at 4 hospitals in Wenzhou between January 2007 and August 2015, TCN2 gene polymorphisms (rs1801198, C/G; rs9606756, A/G) in peripheral blood were determined using improved multiple ligase detection reaction (iMLDR). The Simplified Crohn's Disease Activity Index (CDAI) was applied to evaluate activity of CD. Eighty-eight CD patients and 138 age- and sex-matched controls were randomly selected from all the study subjects using computer-generated random numbers, in whom serum Hcy level was tested by enzymatic cycling assay, folate and vitamin B12 levels were examined by chemiluminescence immunoassay.

RESULTS

(1) The mutant allele (G) and genotype (CG+ GG) of rs1801198 were not significantly different between the CD group and the control group (both P>0.05), but more prevalent in patients with stricturing CD than in controls (65.75% vs 56.10%, 93.15% vs 82.40%, both P<0.05). The frequencies of mutant allele (G) and heterozygous genotype (AG) of rs9606756 were higher in CD patients than in controls (2.44% vs 1.05%, 4.89% vs 2.09%, both P<0.05), also higher in patients with stricturing CD or ileocolonic CD compared with controls (stricturing CD: 4.79% vs 1.05%, 9.59% vs 2.09%; ileocolonic CD: 3.18% vs 1.05%, 6.36% vs 2.09%; all P<0.05). The two polymorphic loci (rs1801198 and rs9606756) were shown to be in a weak linkage disequilibrium. The frequency of haplotype (GG) was higher in the CD patients than in the controls (2.23% vs 0.81%, P<0.05). (2) When compared with the controls, the serum Hcy level was higher in the CD patients (P=0.023), whereas the folate and vitamin B12 levels were decreased in the CD patients (both P<0.001). The prevalence of hyperhomocysteinemia (Hcy >15 μmol/L), folate deficiency (folate <4 μg/L) and vitamin B12 deficiency (<203 ng/L) were higher in the CD patients than in the controls (18.18% vs 4.35%, 27.27% vs 5.07%, 31.82% vs 5.07%, all P<0.01). Compared to the patients at remission stage (CDAI<5), the serum Hcy level was increased in those at active stage (CDAI≥5) (P=0.005), while the folate and vitamin B12 levels were decreased in the patients ate active stage (both P<0.05). (3) According to the results of multivariate linear regression analysis, average Hcy level in the CD patients was negatively associated with folate level (β=-0.494, P<0.001), while positively correlated with percentage of neutrophils (β=0.294, P=0.004). Unconditional Logistic regression showed that both folate deficiency and vitamin B12 deficiency were independent risk factors for CD (OR=5.415, OR=7.112, both P<0.001).

CONCLUSIONS

TCN2 rs1801198 mutation might be associated with increased risk of stricturing CD. TCN2 rs9606756 mutation might be a potential functional locus to affect CD susceptibility. Individuals carrying the haplotype (GG) formed by TCN2 (rs1801198 and rs9606756) seem to be at higher risk of developing CD. Hyperhomocysteinemia, folate deficiency, and vitamin B12 deficiency are prevalent in this cohort of CD patients of Han ethnicity from Zhejiang province. Both folate deficiency and vitamin B12 deficiency are independent risk factors for CD.

Induction of melasma by 1064-nm Q-switched neodymium:yttrium-aluminum-garnet laser therapy for acquired bilateral nevus of Ota-like macules (Hori nevus): A study on related factors in the Chinese population

Laser treatment has emerged as a common treatment modality for acquired bilateral nevus of Ota-like macules (ABNOM). To identify the ratio of melasma induction and exacerbation before and after laser therapy for ABNOM and to observe the risk factors related to the induction and exacerbation of melasma by laser therapy, we analyzed related factors of 1268 adult Chinese patients who underwent 1064-nm Q-switched neodymium:yttrium-aluminum-garnet (Nd:YAG) laser (QNYL) treatment using case series and case-control studies. Overall, 24.0% of the ABNOM patients had mixed melasma. Among the ABNOM patients without melasma, after laser therapy the development of melasma was more frequently noted in patients older than 35 years (P < 0.0001), as well in patients whose ABNOM was less than 10 cm(2) (P = 0.027), ABNOM were light (similar to yellow-brown) in color (P = 0.021) and skin types were closer to type IV (P < 0.0001). New melasma lesions also appeared most frequently in the zygomatic region (P < 0.0001). Among the ABNOM patients with melasma, 89.5% experienced worsening of their melasma, irrespective of their related factors above. We concluded that the risk of inducing melasma is great after 1064-nm QNYL treatment in ABNOM patients, and particularly in the patients with both ABNOM and melasma. ABNOM patients should be treated as early as possible and before the age of 35 years.

A novel 4/6-type alpha-conotoxin ViIA selectively inhibits nAchR α3β2 subtype

Conotoxins (CTxs) are typically small peptides composed of 12-50 amino acid residues with 2-5 disulfide bridges. Most of them potently and selectively target a wide variety of ion channels and membrane receptors. They are highly valued as neuropharmacological probes and in pharmaceutical development. In this work, a novel α4/6-CTx named ViIA (RDCCSNPPCAHNNPDC-NH2) was identified from a cDNA library of the venom ducts of Conus virgo (C. virgo). ViIA was then synthesized chemically and its disulfide connectivity was identified as 'C(1)-C(3), C(2)-C(4)'. Its molecular targets were further assessed using two-electrode voltage clamping. The results indicated that ViIA selectively inhibited nicotinic acetylcholine receptor (nAChR) α3β2 subtype with an IC50 of 845.5 nM, but did not target dorsal root ganglion sodium (Na(+))-, potassium (K(+))- or calcium (Ca(2+))-ion channels. Further structure-activity relationship analysis demonstrated that Arg(1) and His(11) but not Asp(2) were the functional residues. To the best of our knowledge, ViIA is the first 4/6 α-CTx that selectively inhibits nAChR α3β2 subtype. This finding expands the knowledge of targets of α4/6-family CTxs.

Polyphenols isolated from leaves of Vitis thunbergii var. taiwaniana regulate APP related pathway

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by the accumulation of amyloid plaques and neurofibrillary tangles in the brain. The major component of the plaques, amyloid-β (Aβ), is generated from amyloid-β precursor protein (APP) by β- and γ-secretase-mediated cleavages. Multiple lines of evidence demonstrate that overproduction/accumulation of Aβ in vulnerable brain regions is a primary cause of the pathogenesis of AD. Among the twelve polyphenols isolated from the leaf extracts of Vitis thunbergii var. taiwaniana (VTT), stenophyllol C, stenophyllol B, ampelopsin C, vitisin A, and davidiol A were shown to significantly reduce both Aβ40 and Aβ42 levels in N2a695 cells. Further studies revealed that ampelopsin C and vitisin A reduce Aβ production through inhibiting β-secretase activity, while the effects of the other active polyphenols on reducing Aβ generation are through different mechanisms. These results suggest that VTT extracts may be beneficial for AD prevention and treatment.

Increasing production of matrix metalloproteinases, tumor necrosis factor-α, vascular endothelial growth factor and prostaglandin E2 in rheumatoid arthritis synovial fibroblasts by different adiponectin isoforms in a concentration-dependent manner

Adipokines have been known to play a significant role in rheumatic disease via synovial fibroblasts. However, to date, the concentration effects of adiponectin isoforms on the pathophysiology of rheumatoid arthritis (RA) have not been extensively studied. Therefore, the present study examined the different effects of the adiponectin isoforms on rheumatoid arthritis synovial fibroblasts (RASF) and investigated the relations between the concentration of individual adiponectin isoforms and the production of the inflammatory factors of RASF. Articular synovial tissues were obtained from the patients fulfilled with diagnostic criteria of RA, and health people. RASF and human fibroblast&mdash;like synoviocytes (HFLS) were isolated and cultured. They were stimulated with increasing concentrations of 25 &#956;g/ml, 50 &#956;g/ml, and 100&#956;g/ml of different human adiponectin isoforms. The levels of matrix metalloproteinase (MMP)&mdash;3, MMP&mdash;10, tumor necrosis factor (TNF)&mdash;&#945;, vascular endothelial growth factor (VEGF), and prostaglandin E2 (PGE2) in culture supernatants were measured by immunoassays. The results showed the levels of MMP&mdash;3, MMP&mdash;10, TNF&mdash;&#945;, VEGF and PGE2 were significantly increased in RASF which were treated with individual adiponectin isoforms compared to untreated RASF (p&lt;0.01), and the increases also had significances compared to HFLS which were treated with the same conditions (p&lt;0.05). Moreover, the effect of HMW (high molecular weight)/ MMW (middle molecular weight) was the strongest among them. In conclusion, all three adiponectin isoforms may contribute to proinflammatory effect by stimulating the production of MMP&mdash;3, MMP&mdash;10, TNF&mdash;&#945;, VEGF and PGE2 of RASF in a concentration&mdash;dependent manner. HMW/MMW adiponectin could play an important role in matrix destroying and synovial vascular creating of the pathology of RA.

Peroxynitrite decomposition catalyst prevents matrix metalloproteinase-9 activation and neurovascular injury after hemoglobin injection into the caudate nucleus of rats

Hemoglobin (Hb) is a major constituent of blood and a potent mediator of oxidative or nitrative stress after intracerebral hemorrhage (ICH). Our previous study demonstrated that Hb could induce abundant peroxynitrite (ONOO(-)) formation in vivo, which may be involved in the blood-brain barrier (BBB) disruption, however, the drug intervention is absent and also the underlying mechanism. Using an experimental stroke model by injecting Hb into the caudate nucleus of male Sprague-Dawley rats, we assessed the role of ONOO(-) decomposition catalyst, 5,10,15,20-tetrakis (4-sulfonatophenyl) porphyrinato iron(III) [FeTPPS] in the activation of MMP-9 and Hb-induced neurovascular injuries. 3-Nitrotyrosine (3-NT, as an index of ONOO(-) formation) and NF-κB expression was measured by western blot (WB) and immunohistochemistry (IHC)/immunofluorescence (IF). Activity of MMP was evaluated by in situ zymography. Neurovascular injury was assessed using zonula occludens-1 (ZO-1) by WB and IF, fibronectin (FN) and neuron-specific nuclear protein (NeuN) IHC. Perihematomal cell death was determined by TUNEL assay. Behavioral outcome was measured by modified neurological severity score (mNSS) test. At the injured striata, profuse 3-NT was produced and mainly expressed in neutrophils and microglia/macrophages. 3-NT formation significantly colocalized with nuclear factor-κB (NF-κB) expression. In situ zymography showed that gelatinase activity was mostly co-localized with neurons and blood vessel walls and partly with neutrophils and microglia/macrophages. Enhanced 3-NT production, NF-κB induction and MMP-9 activation were obviously reduced after FeTPPS treatment. Hb-induced injury to tight junction protein (ZO-1), basal lamina of FN-immunopositive microvasculature and neural cells was evidently ameliorated by FeTPPS. In addition, apoptotic cell numbers as well as behavioral deficits were also improved. The present study shows that the administration of the ONOO(-) decomposition catalyst FeTPPS protects against Hb-induced neurovascular injuries and improves neurological function, which possibly in part by suppressing MMP-9 activation.

Nanostructure characterisation of flow-formed Cr-Mo-V steel using transmission Kikuchi diffraction technique

Nowadays flow-forming has become a desired near net shape manufacturing method as it provides excellent mechanical properties with improved surface finish and significant manufacturing cost reduction. However, the material is subjected to excessive plastic deformation during flow-forming process, generating a very fine and complex microstructure. In addition, the intense dislocation density and residual stress that is generated in the component during processing makes the microstructure characterisation using conventional micro-analytical tools challenging. Thus, the microstructure/property relationship study in such a material is rather difficult. In the present study a flow-formed Cr-Mo-V steel nanostructure and crystallographic texture were characterised by means of Transmission Kikuchi Diffraction (TKD). Here, TKD is shown to be a powerful technique in revealing very fine martensite laths within an austenite matrix. Moreover, fine precipitates in the order of 20-70 nm on the martensite lath boundaries were clearly imaged and characterised. This greatly assisted in understanding the preferable site formation of the carbides in such a complex microstructure. The results showed that the actual TKD spatial resolution was in the range of 5-10 nm using 25 kV for flow-formed Cr-Mo-V steel.

U12, a UDCA derivative, acts as an anti-hepatoma drug lead and inhibits the mTOR/S6K1 and cyclin/CDK complex pathways

U12, one of 20 derivatives synthesized from ursodeoxycholic acid (UDCA), has been found to have anticancer effects in liver cancer cell lines (SMMC-7721 and HepG2) and to protect normal liver cells from deoxycholic acid (DCA) damage (QSG-7701). Its anticancer mechanism was investigated using computer-aided network pharmacology and comparative proteomics. Results showed that its anti-malignancy activities were activated by mTOR/S6K1, cyclinD1/CDK2/4 and caspase-dependent apoptotic signaling pathways in hepatocellular carcinoma cells (HCC). The action of U12 may be similar to that of rapamycin. Animal testing confirmed that U12 exerted better anti-tumor activity than UDCA and had less severe side effects than fluorouracil (5-Fu). These observations indicate that U12 differs from UDCA and other derivatives and may be a suitable lead for the development of compounds useful in the treatment of HCC.

Structure elucidation and biological activity of two new trichothecenes from an endophyte, Myrothecium roridum

Worldwide, many different grains are infected by various fungi that may produce trichothecene mycotoxins. Fungi that produce trichothecenes, as well as the trichothecenes themselves, are potential problems for public health. On the other hand, trichothecenes possess multiple biological activities. Reduced toxicity may result in their applications in the pharmaceutical field. Two new trichothecenes along with seven known trichothecenes were isolated from an endophyte of the herb plant Ajuga decumbens. Their structures were deduced from 1D and 2D NMR data. The results of MTT assays revealed that new trichothecene 2',3'-epoxymyrothecine A, 1, and myrothecine A, 3, exhibited much lower toxicity compared to other trichothecenes. New trichothecene 2',3'-epoxymyrothecine A, 1, could induce phosphorylation of JNK (c-Jun N-terminal protein kinase) protein and the PARP (poly ADP-ribose polymerase) cleavage, and eventually induce apoptosis in cancer cells. These results point out the possibility for application of trichothecenes as chemotherapeutic agent.

Myrotheciumones: bicyclic cytotoxic lactones isolated from an endophytic fungus of Ajuga decumbens

Two new bicyclic lactones, myrotheciumones A (1) and B (2) which possessed a rare ring-fusion system were isolated from Myrothecium roridum (M. roridum), an endophytic fungus of the medicinal herb plant Ajuga decumbens (A. decumbens) via an in vitro cytotoxicity assay. Structures were deduced from 1D and 2D NMR (Nuclear magnetic resonance) data. Myrotheciumone A's in vitro cytotoxicity and apoptotic activity were evaluated and myrotheciumone A was shown to exert cytotoxicity via inducing apoptosis in cancer cell line.

Knockdown of MMP11 inhibits proliferation and invasion of gastric cancer cells

Matrix metalloproteinase 11 (MMP11 or stromelysin-3) has recently been reported to play a crucial role in the development and progression of multiple malignancies. The aim of this study was to investigate the function of MMP11 expression in human gastric adenocarcinoma (GAC). Using immunohistochemistry assay, we studied the expression level of MMP11 in GAC and adjacent non-cancerous tissues (ANCT). The association between MMP11 expression and tumor size and pathological grade, as well as metastatic potential was analyzed. Through small hairpin RNA (shRNA)-mediated MMP11 knockdown in SGC-7901 GAC cells, we observed the changes of the biological behaviors of GAC cells. Our results indicated that the rate of positive expression of MMP11 was higher in GAC tissues than in ANCT (55.0 vs 30.0 percent, P=0.025). MMP11 expression had no association with the factors of age or gender of the GAC patients, or the size, pathological staging and lymph node metastases of the tumors (each P greater than 0.05). Furthermore, MMP11 knockdown inhibited the proliferative activities and invasive potential of SGC-7901 GAC cells with decreased expression of IGF-1, PCNA and VEGF. Taken together, our findings demonstrated that MMP11 expression was increased in GAC tissues, but did not correlate with the clinicopathologic features. Knockdown of MMP11 expression could inhibit the proliferation and invasion of GAC cells probably through down-regulation of the IGF-1 signaling pathway, suggesting that MMP11 might be a potential therapeutic target for the treatment of gastric cancer.

Progress in treatment of esophageal cancer by traditional Chinese medicine

Esophageal cancer is a common malignant tumor. Surgery is the radical treatment for esophageal cancer. However, only patients with early stage disease are suitable for surgery. Despite the improvement in radiotherapy and chemotherapy in recent years, the 5-year survival rate of esophageal cancer remains low. In view of adverse side effects associated with surgery, radiotherapy, and chemotherapy, traditional Chinese medicine (TCM) can be used to promote the recovery of postoperative patients and integrated into Western medicine treatment regimens. This article summarizes recent progress in treatment of esophageal cancer by TCM in terms of etiology and pathogenesis, TCM treatment, integrated TCM and Western medicine treatment, and mechanisms of TCM treatment.

Kanglaite injection combined with FOLFOX4 regimen for the treatment of advanced colorectal cancer: An analysis of 20 cases

AIM: To evaluate the efficacy and toxicity of Kanglaite injection combined with FOLFOX4 regimen in the treatment of advanced colorectal cancer.

METHODS: In total, 40 patients with advanced colorectal cancer were randomly divided into treatment group and control group. The control group was treated using the FOLFOX4 regimen, and the treatment group were treated using the FOLFOX4 regimen combined with intravenous infusion of Kanglaite injection. After two cycles of therapy, the efficacy and toxicity were evaluated.

RESULTS: The objective response rate and disease control rate were higher in the treatment group than in the control group, but the differences were not significant (25.0% vs 20.0%, P > 0.05; 85.0% vs 75.0%, P > 0.05). The stable rate of TCM syndromes after chemotherapy was 85.0% for the treatment group and 50.0% for the control group (P < 0.05). KPS score and body weight increased significantly in the treatment group after therapy (both P < 0.05). QOL score did not differ significantly between the two groups. After therapy, the numbers of T lymphocytes (CD3+), T-assisted, induced lymphocytes (CD3+CD4+) and NK cells (CD16+CD56+) increased in the treatment group, but decreased in the control group (all P < 0.05). Leucopenia incidence in the treatment group was lower than that in the control group (P < 0.05). The incidences of other adverse reactions showed no significant differences between the two groups.

CONCLUSION: Kanglaite injection combined with FOLFOX4 regimen can improve physical condition, enhance immune function, and reduce chemotherapy toxicity in the treatment of advanced colorectal cancer.

Lack of association between Human Oxoguanine Glycosylase 1 (hOGG1) S326C polymorphism and the risk of gastric cancer: a meta-analysis

Results from published studies on the association of Human Oxoguanine Glycosylase 1 (hOGG1) S326C genetic polymorphism with the risk of gastric cancer are inconsistent. We performed a meta-analysis to summarize the possible association. Eleven case-control studies including 2168 cases and 4058 controls were identified from electronic databases (Pubmed, Elsevier Science Direct, Chinese National Knowledge Infrastructure (CNKI), Chinese Biomedical Literature Database (CBM), and the Chinese database, Wanfang). No significant association between hOGG1 S326C genetic polymorphism and risk of gastric cancer was observed in the overall analysis. In the stratified analysis based on ethnicity, still no significant association was observed in Europeans, Asians, or Brazilians. This meta-analysis provided evidence that hOGG1 S326C genetic polymorphism was not associated with increased risk of gastric cancer. However, additional studies with large sample size and better study designs are warranted to verify our finding.