Clinical presentation and characteristics of pelvic floor myofascial pain in patients presenting with constipation.

BACKGROUND: Patients with pelvic floor myofascial pain (PFMP) have puborectalis tenderness on digital rectal examination (DRE). Little is known about its significance to anorectal function in patients presenting with constipation. AIM: To characterize demographics, clinical characteristics, findings on anorectal manometry (ARM), diagnosis of rectal evacuation disorder (RED), colonic transit [normal (NTC) or slow (STC)], and imaging in constipated patients with PFMP and compare these features to constipation without PFMP. METHODS: We performed an electronic medical records review of patients with constipation evaluated by a single gastroenterologist between January 2008 and February 2019. Patients with PFMP were compared to controls with constipation but without PFMP (1:2 ratio). KEY RESULTS: A total of 98 PFMP cases and 196 controls were identified. Constipated patients with PFMP were more likely to have RED [OR 7.59 (3.82-15.09), P < .01]; controls were more likely to have either NTC [OR 4.25 (1.45-12.42), P < .01] or STC [OR 3.57 (1.45-8.78), P < .01]. RED in patients with PFMP is supported by comparison to controls: On DRE, they had increased resting tone [OR 2.25 (1.33-3.83), P < .01] and paradoxical contraction of the puborectalis upon simulated evacuation [OR 3.41 (1.94-6.00), P < .01]; on ARM, they had higher maximum resting pressure (102.9 mmHg vs 90.7 mmHg, P < .01) and lower rectoanal pressure gradient (-39.4 mmHg vs -24.7 mmHg, P < .01). CONCLUSIONS/INFERENCES: In constipated patients, PFMP is highly associated with RED. Its presence provides a valuable clue regarding the etiology of a patient's constipation; it should be assessed in all patients with constipation and should also be an additional target for management.

Dietary fat alters the response of hypothalamic neuropeptide Y to subsequent energy intake in broiler chickens.

Dietary fat affects appetite and appetite-related peptides in birds and mammals; however, the effect of dietary fat on appetite is still unclear in chickens faced with different energy statuses. Two experiments were conducted to investigate the effects of dietary fat on food intake and hypothalamic neuropeptides in chickens subjected to two feeding states or two diets. In Experiment 1, chickens were fed a high-fat (HF) or low-fat (LF) diet for 35 days, and then subjected to fed (HF-fed, LF-fed) or fasted (HF-fasted, LF-fasted) conditions for 24 h. In Experiment 2, chickens that were fed a HF or LF diet for 35 days were fasted for 24 h and then re-fed with HF (HF-RHF, LF-RHF) or LF (HF-RLF, LF-RLF) diet for 3 h. The results showed that chickens fed a HF diet for 35 days had increased body fat deposition despite decreasing food intake even when the diet was altered during the re-feeding period (P<0.05). LF diet (35 days) promoted agouti-related peptide (AgRP) expression compared with HF diet (P<0.05) under both fed and fasted conditions. LF-RHF chickens had lower neuropeptide Y (NPY) expression compared with LF-RLF chickens; conversely, HF-RHF chickens had higher NPY expression than HF-RLF chickens (P<0.05). These results demonstrate: (1) that HF diet decreases food intake even when the subsequent diet is altered; (2) the orexigenic effect of hypothalamic AgRP; and (3) that dietary fat alters the response of hypothalamic NPY to subsequent energy intake. These findings provide a novel view of the metabolic perturbations associated with long-term dietary fat over-ingestion in chickens.

Leucine alleviates dexamethasone-induced suppression of muscle protein synthesis via synergy involvement of mTOR and AMPK pathways.

Glucocorticoids (GCs) are negative muscle protein regulators that contribute to the whole-body catabolic state during stress. Mammalian target of rapamycin (mTOR)-signalling pathway, which acts as a central regulator of protein metabolism, can be activated by branched-chain amino acids (BCAA). In the present study, the effect of leucine on the suppression of protein synthesis induced by GCs and the pathway involved were investigated. In vitro experiments were conducted using cultured C2C12 myoblasts to study the effect of GCs on protein synthesis, and the involvement of mTOR pathway was investigated as well. After exposure to dexamethasone (DEX, 100 µmol/l) for 24 h, protein synthesis in muscle cells was significantly suppressed (P<0.05), the phosphorylations of mTOR, ribosomal protein S6 protein kinase 1 (p70s6k1) and eukaryotic initiation factor 4E binding protein 1 (4EBP1) were significantly reduced (P<0.05). Leucine supplementation (5 mmol/l, 10 mmol/l and 15 mmol/l) for 1 h alleviated the suppression of protein synthesis induced by DEX (P<0.05) and was accompanied with the increased phosphorylation of mTOR and decreased phosphorylation of AMPK (P<0.05). Branched-chain amino transferase 2 (BCAT2) mRNA level was not influenced by DEX (P>0.05) but was increased by leucine supplementation at a dose of 5 mmol/l (P<0.05).

SPLUNC1 Is a Significant Marker in Pleural Effusion from Lung Cancer Compared to Tuberculosis.

SPLUNC1 (Short palate, lung and nasal epithelium clone1) protein is an abundant secretory product of epithelia present throughout the conducting airways. Although its function is still not fully known, most studies have focused on its defensive effect in the infection of human airways and its potential to serve as a molecular marker for lung cancer. In this study, we further evaluated the SPLUNC1 expression in patients with lung disease to explore its role in cancer or tuberculosis at the protein level. We generated a panel of antibodies by using protein from a eukaryotic expression system as the immunogen to mice. It was the panel of SPLUNC1 monoclonal antibodies that allowed us to comparatively determine SPLUNC1 protein in lung cancer and tuberculosis infection by detecting sera and pleural effusion other than airway surface. The results showed that the SPLUNC1 level was not significantly changed either from sera of lung cancer or control. There was a significant increase in pleural effusion from lung cancer when compared to tuberculosis. These results indicate that SPLUNC1 may be a useful marker for tracing lung cancer cells, based on its epithelial origin property in pleural effusion.

Common variant rs7597774 in ADD2 is associated with dilated cardiomyopathy in Chinese Han population.

Two polymorphisms, rs7597774 and rs1739843 in ADD2 and HSPB7 respectively, were found to be associated with dilated cardiomyopathy (DCM) in European cohorts but the results were not validated in the Chinese Han population. We aimed to test the association of the two variants with DCM in a cohort of Chinese Han population. DCM (399) and control (1384) individuals were identified from the GeneID database in China, and DNA was isolated from peripheral blood lymphocytes for genotyping. Alleles were amplified by PCR, and amplicons harboring polymorphisms rs1739843 and rs7597774 were directly genotyped using high-resolution melting analysis. Statistical analysis was subsequently performed to evaluate the association of the variants with DCM. Allelic analysis demonstrated that rs7597774 was significantly related to DCM (P -adj = 0.0157), and an increased risk of DCM was specifically associated with the minor allele A (OR = 1.582). High-grade cardiac dysfunction (NYHA III/IV) was a clinical parameter significantly associated with the rs7597774 genotypes AA + AC relative to genotype CC (P = 0.021). Furthermore, DCM patients with the rs7597774 genotype AA tended to undergo more invasive medical interventions than those with the genotype CC (P = 0.008). No association was detected between rs1739843 and DCM under any allelic (P -adj = 0.407, OR = 0.920) or genotypic model. In the Chinese Han population, rs7597774 but not rs1739843 was found to be associated with DCM. This study is the first to demonstrate that underlying genotypes of rs7597774 may assist in assessing the heart functional status of DCM patients and also in the prediction of the benefit of particular therapies for these patients.

Genome-wide association and sequencing studies on colorectal cancer.

Colorectal cancer is a leading cause of morbidity and mortality worldwide. Understanding its genetic mechanisms is key to improving risk prediction, prognostication and treatment. Results from genome-wide association studies have engendered a growing list of colorectal cancer susceptibility genes whereas the application of genome-wide mutational analysis has enabled the depiction of mutational landscape of colorectal cancer at high resolution. The development of novel technologies, such as metagenomic and single-cell sequencing, is expected to have positive impact on future genetic studies. However, challenges remain to address the changing epidemiology of colorectal cancer, issues on genetic testing, and clinical utilization of genomic data.

A novel crosstalk between two major protein degradation systems: regulation of proteasomal activity by autophagy.

Eukaryotes have two major intracellular protein degradation pathways, namely the ubiquitin-proteasome system (UPS) and autophagy. Inhibition of proteasomal activities has been previously shown to induce autophagy, indicating a coordinated and complementary relationship between these two systems. However, little is known about the regulation of the UPS by autophagy. In this study, we showed for the first time that proteasomes were activated in response to pharmacological inhibition of autophagy as well as disruption of autophagy-related genes by RNA interference under nutrient-deficient conditions in cultured human colon cancer cells. The induction was evidenced by the increased proteasomal activities and the upregulation of proteasomal subunits, including the proteasome ß5 subunit, PSMB5. Co-inhibition of the proteasome and autophagy also synergistically increased the accumulation of polyubiquitinated proteins. Collectively, our findings suggest that proteasomes are activated in a compensatory manner for protein degradation upon autophagy inhibition. Our studies unveiled a novel regulatory mechanism between the two protein degradation pathways.

FK-16 derived from the anticancer peptide LL-37 induces caspase-independent apoptosis and autophagic cell death in colon cancer cells.

Host immune peptides, including cathelicidins, have been reported to possess anticancer properties. We previously reported that LL-37, the only cathelicidin in humans, suppresses the development of colon cancer. In this study, the potential anticancer effect of FK-16, a fragment of LL-37 corresponding to residues 17 to 32, on cultured colon cancer cells was evaluated. FK-16 induced a unique pattern of cell death, marked by concurrent activation of caspase-independent apoptosis and autophagy. The former was mediated by the nuclear translocation of AIF and EndoG whereas the latter was characterized by enhanced expression of LC3-I/II, Atg5 and Atg7 and increased formation of LC3-positive autophagosomes. Knockdown of Atg5 or Atg7 attenuated the cytotoxicity of FK-16, indicating FK-16-induced autophagy was pro-death in nature. Mechanistically, FK-16 activated nuclear p53 to upregulate Bax and downregulate Bcl-2. Knockdown of p53, genetic ablation of Bax, or overexpression of Bcl-2 reversed FK-16-induced apoptosis and autophagy. Importantly, abolition of AIF/EndoG-dependent apoptosis enhanced FK-16-induced autophagy while abolition of autophagy augmented FK-16-induced AIF-/EndoG-dependent apoptosis. Collectively, FK-16 induces caspase-independent apoptosis and autophagy through the common p53-Bcl-2/Bax cascade in colon cancer cells. Our study also uncovered previously unknown reciprocal regulation between these two cell death pathways.

Dysregulation and crosstalk of cellular signaling pathways in colon carcinogenesis.

Multiple intracellular signaling pathways, such as Wnt/ß-catenin signaling, epidermal growth factor receptor/Ras signaling, and p53 signaling are frequently dysregulated in colorectal cancer. Recent evidence also points to the involvement of signaling pathways in the developmental process, including Notch signaling, Hedgehog signaling, and Hippo signaling. Dysregulation of these signaling pathways contribute to the acquisition of malignant phenotypes, including unchecked cell cycle progression, evasion of apoptosis, induction of genetic instability, and enhanced invasiveness and metastasis. Understanding their relative importance and crosstalk will provide a rational basis for anticancer drug development.

Host immune defense peptide LL-37 activates caspase-independent apoptosis and suppresses colon cancer.

Cathelicidins are a family of bacteriocidal polypeptides secreted by macrophages and polymorphonuclear leukocytes (PMN). LL-37, the only human cathelicidin, has been implicated in tumorigenesis, but there has been limited investigation of its expression and function in cancer. Here, we report that LL-37 activates a p53-mediated, caspase-independent apoptotic cascade that contributes to suppression of colon cancer. LL-37 was expressed strongly in normal colon mucosa but downregulated in colon cancer tissues, where in both settings its expression correlated with terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling-positive apoptotic cells. Exposure of colon cancer cells to LL-37 induced phosphatidylserine externalization and DNA fragmentation in a manner independent of caspase activation. Apoptogenic function was mediated by nuclear translocation of the proapoptotic factors, apoptosis-inducing factor (AIF) and endonuclease G (EndoG), through p53-dependent upregulation of Bax and Bak and downregulation of Bcl-2 via a pertussis toxin-sensitive G-protein-coupled receptor (GPCR) pathway. Correspondingly, colonic mucosa of cathelicidin-deficient mice exhibited reduced expression of p53, Bax, and Bak and increased expression of Bcl-2 together with a lower basal level of apoptosis. Cathelicidin-deficient mice exhibited an increased susceptibility to azoxymethane-induced colon tumorigenesis, establishing pathophysiologic relevance in colon cancer. Collectively, our findings show that LL-37 activates a GPCR-p53-Bax/Bak/Bcl-2 signaling cascade that triggers AIF/EndoG-mediated apoptosis in colon cancer cells.

Co-inhibition of microRNA-10b and microRNA-21 exerts synergistic inhibition on the proliferation and invasion of human glioma cells.

MicroRNAs (miRNAs) are small non-coding RNAs that function as negative gene regulators. Alterations in the expression of miRNAs have been implicated in the pathogenesis and development of most human malignancies. Recent data indicate that microRNA-21 and microRNA-10b are significantly elevated in glioblastoma multiforme (GBM) suggesting their role in the regulation of multiple genes associated with cancer. In this study, U87MG human glioblastoma cells were treated with miRNA inhibitors targeting miR-10b and miR-21, alone or in combination. The results showed that the miR-21 inhibitor additively interacted with miR-10b inhibitor on U87MG cells. The 50% inhibitory concentration values were dramatically decreased in cells treated with the combination of miR-10b and miR-21 inhibitors. Furthermore, inhibitors synergistically combined, enhanced apoptosis significantly and reduced invasion ability assessed by flow cytometry and Transwell migration assay. Thus, the miR-21 inhibitor may interrupt the activity of EGFR pathways, increasing PDCD4 and TPM1 expression and reducing MMP activities, independently of PTEN status. Meanwhile, miR-10b inhibitor reduced by Twist proceeds to inhibit translation of the mRNA encoding HOXD10 leading to the increase of the expression of the well-characterized pro-metastatic gene RHOC. Taken together, these data strongly suggest that a combination of miR-21 inhibitor and miR-10b inhibitor could be an effective therapeutic strategy for controlling the growth of GBM by inhibiting oncogene expression and overexpressing tumor suppressor genes. Moreover, a regulatory strategy based on the combination of miRNA inhibitors may provide insights into the mechanisms of the modulation of signaling genes involved in tumor cell apoptosis and invasiveness.

Hydrogen sulfide lowers proliferation and induces protective autophagy in colon epithelial cells.

Hydrogen sulfide (H(2)S) is a gaseous bacterial metabolite that reaches high levels in the large intestine. In the present study, the effect of H(2)S on the proliferation of normal and cancerous colon epithelial cells was investigated. An immortalized colon epithelial cell line (YAMC) and a panel of colon cancer cell lines (HT-29, SW1116, HCT116) were exposed to H(2)S at concentrations similar to those found in the human colon. H(2)S inhibited normal and cancerous colon epithelial cell proliferation as measured by MTT assay. The anti-mitogenic effect of H(2)S was accompanied by G(1)-phase cell cycle arrest and the induction of the cyclin-dependent kinase inhibitor p21(Cip). Moreover, exposure to H(2)S led to features characteristic of autophagy, including increased formation of LC3B(+) autophagic vacuoles and acidic vesicular organelles as determined by immunofluorescence and acridine orange staining, respectively. Abolition of autophagy by RNA interference targeting Vps34 or Atg7 enhanced the anti-proliferative effect of H(2)S. Further mechanistic investigation revealed that H(2)S stimulated the phosphorylation of AMP-activated protein kinase (AMPK) and inhibited the phosphorylation of mammalian target of rapamycin (mTOR) and S6 kinase. Inhibition of AMPK significantly reversed H(2)S-induced autophagy and inhibition of cell proliferation. Collectively, we demonstrate that H(2)S inhibits colon epithelial cell proliferation and induces protective autophagy via the AMPK pathway.

Lentiviral expression of anti-microRNAs targeting miR-27a inhibits proliferation and invasiveness of U87 glioma cells.

Glioma is a highly fatal malignant disease and its treatment options are limited. microRNAs represent a novel target for the treatment of cancer. In the present study, we used a lentiviral vector to stably express anti-microRNAs targeting the oncogenic miR-27a in U87 glioma cells. The stable expression of anti-miR-27a significantly reduced the proliferation and increased the accumulation of U87 cells in the sub-G1 phase as determined by Cell Counting kit-8 (CCK-8) assays and flow cytometry, respectively. Results from the Matrigel transwell assay also indicated that the inhibition of miR-27a substantially impaired the invasiveness of U87 cells. By combining bioinformatic and proteomic approaches, we identified the mRNAs of 8 proteins upregulated in anti-miR-27a-expressing U87 cells as putative direct targets of miR-27a. Collectively, these data suggest that the lentiviral expression of anti-miR-27a is a feasible approach for the suppression of malignant phenotypes of glioma cells.

Mice overexpressing latent TGF-beta1 are protected against renal fibrosis in obstructive kidney disease.

Transforming growth factor (TGF)-beta1, once activated, binds to its receptors and mediates renal fibrosis via the downstream Smad signaling pathway. We reported here that mice overexpressing latent TGF-beta1 in keratinocytes were protected against renal fibrosis in a model of obstructive kidney disease. In normal mice, both transgenic (Tg) and wild-type (WT) mice had normal renal histology and function, despite a 10-fold increase in plasma latent TGF-beta1 in Tg mice. A severe renal fibrosis was developed in WT mice at 7 days after urinary obstruction. Unexpectedly, renal fibrosis was prevented in Tg mice, although levels of latent TGF-beta1 in both circulation and renal tissues remained high. Compared with the WT mice, quantitative real-time PCR showed that upregulation of renal alpha-smooth muscle actin (SMA), collagen I, and collagen III mRNA was inhibited in Tg mice (60-70% reduced, all P < 0.01). These were further confirmed by immunohistochemistry with a marked inhibition of tubulointerstitial accumulation of alpha-SMA+ fibroblasts, collagen I, and collagen III matrix in Tg mice (all P < 0.001). Further studies showed that inhibition of renal fibrosis in Tg mice was associated with a significant reduction in renal TGF-beta1 and CTGF (60% reduced, P < 0.05), an increase in renal Smad7, a suppression of TSP-1 (a critical factor for TGF-beta1 activation), and an inhibition of Smad2/3 activation (all P < 0.001). In conclusion, latent TGF-beta may play a protective role in renal fibrosis. Inhibition of renal TGF-beta1 expression and activation, thereby blocking the downstream TGF-beta signaling pathway, may be a critical mechanism by which latent TGF-beta1 protects against renal fibrosis.

Latent TGF-beta1 protects against crescentic glomerulonephritis.

Despite the critical role that TGF-beta plays in renal fibrosis, transgenic mice that overexpress human latent TGF-beta1 in the skin exhibit normal renal histology and function even though circulating levels of latent TGF-beta1 are an order of magnitude higher than wild-type animals. In fact, latent TGF-beta1 seems to protect against renal inflammation in a model of ureteral obstruction. It is unknown, however, whether latent TGF-beta1 also has this effect in immunologically mediated forms of renal disease such as anti-GBM crescentic glomerulonephritis. We induced anti-GBM disease in wild-type and transgenic mice overexpressing latent TGF-beta1 in keratinocytes. After 14 days, wild-type mice developed progressive crescentic glomerulonephritis with severe renal inflammation and fibrosis. In transgenic mice, proteinuria was reduced by 50%, renal function was preserved, and the formation of glomerular crescents was suppressed by 70%. In addition, transgenic animals had reduced renal inflammation, evidenced by a 70% decrease in the accumulation of T cells and macrophages, and reduced expression of renal IL-1beta, TNFalpha, and MCP-1 by 70 to 80%. Progressive renal fibrosis was also prevented in the transgenic mice, and these protective effects were associated with elevated levels of latent, but not active, TGF-beta1 in plasma and renal tissue. Renal Smad7 was up-regulated and both NF-kappaB and TGF-beta/Smad2/3 activation were suppressed. In conclusion, mice overexpressing latent TGF-beta1 in the skin were protected against anti-GBM crescentic glomerulonephritis, possibly via Smad 7-mediated inhibition of NF-kappaB-dependent renal inflammation and TGF-beta/Smad2/3-dependent fibrosis.

Signaling mechanism of TGF-beta1 in prevention of renal inflammation: role of Smad7.

TGF-beta has been shown to play a critical role in anti-inflammation; however, the signaling mechanisms of TGF-beta in anti-inflammatory response remains largely unclear. This study reported that mice that overexpress latent TGF-beta1 on skin are protected against renal inflammation in a model of obstructive kidney disease and investigated the signaling mechanism of TGF-beta1 in inhibition of renal inflammation in vivo and in vitro. Seven days after urinary obstruction, wild-type mice developed severe renal inflammation, including massive T cell and macrophage infiltration and marked upregulation of IL-1beta, TNF-alpha, and intercellular adhesion molecule-1 (all P < 0.001). Surprising, renal inflammation was prevented in transgenic mice. This was associated with an increase in latent TGF-beta1 in circulation (a 10-fold increase) and renal tissues (a 2.5-fold increase). Further studies showed that inhibition of renal inflammation in TGF-beta1 transgenic mice was also associated with a marked upregulation of renal Smad7 and IkappaBalpha and a suppression of NF-kappaB activation in the diseased kidney (all P < 0.01). These in vivo findings suggested the importance of TGF-beta-NF-kappaB cross-talk signaling pathway in regulating renal inflammation. This was tested in vitro in a doxycycline-regulated Smad7-expressing renal tubular cell line. Overexpression of Smad7 was able to upregulate IkappaBalpha directly in a time- and dose-dependent manner, thereby inhibiting NF-kappaB activation and NF-kappaB-driven inflammatory response. In conclusion, latent TGF-beta may have protective roles in renal inflammation. Smad7-mediated inhibition of NF-kappaB activation via the induction of IkBalpha may be the central mechanism by which latent TGF-beta prevents renal inflammation.