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Many studies have focused on the metabolic capacity of human gut microbiota to produce short-chain fatty acids and subsequent effects on host physiology. Given scarce data on how SCFAs produced by gut bacteria participate in cross-feeding to influence community structure and function, we evaluated the potential of SCFAs to modulate human gut microbiota in vitro. We employed anaerobic fecal cultivation in chemically defined medium supplemented with one of nine SCFAs to determine effects on both gut microbial community structure via 16S rRNA sequencing and function via genome reconstruction analysis. Each SCFA displayed significant and unique modulatory potential with respect to the relative abundance of bacterial taxa. Analysis of SCFA-supplemented communities revealed that alterations of individual closely related phylotypes displayed coherent changes, although exceptions were also observed which suggest strain-dependent differences in SCFA-induced changes. We used genome reconstruction to evaluate the functional implications of SCFA-mediated restructuring of fecal communities. We note that some SCFA-supplemented cultures displayed a reduction in the predicted abundance of SCFA producers, which suggests a possible undefined negative feedback mechanism. We conclude that SCFAs are not simply end-products of metabolism but also serve to modulate the gut microbiota through cross-feeding that alters the fitness of specified taxa. These results are important in the identification of prebiotics that elevate specific SCFAs for therapeutic benefit and highlight SCFA consumers as a salient part of the overall metabolic flux pertaining to bacterial fermentative processes.

Introduction: Diabetic nephropathy (DN) and hypertensive nephrosclerosis (HN) represent the most common causes of chronic kidney disease (CKD) and many patients progress to ­end-stage renal disease. Patients are treated primarily through the management of cardiovas­cular risk factors and hypertension; however patients with HN have a more favorable outcome. A noninvasive clinical approach to separate these two entities, especially in hypertensive patients who also have diabetes, would allow for targeted treatment and more appropriate resource allocation to those patients at the highest risk of CKD progression. Meth­ods: In this preliminary study, high-spatial-resolution matrix-assisted laser desorption/ion­ization (MALDI) mass spectrometry imaging (MSI) was integrated with high-mass accuracy MALDI-FTICR-MS and nLC-ESI-MS/MS analysis in order to detect tissue proteins within kidney biopsies to discriminate cases of DN (n = 9) from cases of HN (n = 9). Results: Differences in the tryptic peptide profiles of the 2 groups could clearly be detected, with these becoming even more evident in the more severe histological classes, even if this was not evident with routine histology. In particular, 4 putative proteins were detected and had a higher signal intensity within regions of DN tissue with extensive sclerosis or fibrosis. Among these, 2 proteins (PGRMC1 and CO3) had a signal intensity that increased at the latter stages of the disease and may be associated with progression. Discussion/Conclusion: This preliminary study represents a valuable starting point for a future study employing a larger cohort of patients to develop sensitive and specific protein biomarkers that could reliably differentiate between diabetic and hypertensive causes of CKD to allow for improved diagnosis, fewer biopsy procedures, and refined treatment approaches for clinicians.

Infant formula feeding, compared with human milk, has been associated with development of a distinct infant gut microbiome, but no previous study has examined effects of formula with added sugars. This work examined differences in gut microbiota among 91 Hispanic infants who consumed human milk [at breast (BB) vs. pumped in bottle (BP)] and 2 kinds of infant formula [(traditional lactose-based (TF) vs. lactose-reduced with added sugar (ASF)]. At 1 and 6 months, infant stool was collected to characterize gut microbiota. At 6 months, mothers completed 24-hour dietary recalls and questionnaires to determine infant consumption of human milk (BB vs. BP) or formula (TF vs. ASF). Linear regression models were used to determine associations of milk consumption type and microbial features at 6 months. Infants in the formula groups exhibited a significantly more ‘mature’ microbiome than infants in the human milk groups with the most pronounced differences observed between the ASF vs. BB groups. In the ASF group, we observed reduced log-normalized abundance of Bifidobacteriaceae (TF-BB Mean Difference = −0.71, ASF-BB Mean Difference = −1.10), and increased abundance of Lachnospiraceae (TF-BB Mean Difference = +0.89, ASF-BB Mean Difference = +1.20). We also observed a higher Community Phenotype Index of propionate, most likely produced by Lachnospiraceae, in the ASF group (TF-BB Mean Difference = +0.27, ASF-BB Mean Difference = +0.36). This study provides the first evidence that consumption of infant formula with added sugar may have a stronger association than birth delivery mode, infant caloric intake, and maternal BMI on the infant’s microbiome at 6 months of age.

Molecular interactions between proteins redox partners (cytochromes Р450 3А4, 3А5 and cytochrome b5) within the monooxygenase system, which is known to be involved in drug biotransformation, were investigated. Human cytochromes Р450 3А4 and 3А5 (CYP3A4 and CYP3A5) form complexes with various cytochromes b5: the microsomal (b5mc) and mitochondrial (b5om) forms of this protein, as well as with 2 "chimeric" proteins, b5(om-mc), b5(mc-om). Kinetic constants and equilibrium dissociation constants were determined by the SPR biosensor. Essential distinction between CYP3A4 and CYP3A5 was only observed upon their interactions with cytochrome b5om. Electroanalytical characteristics of electrodes with immobilized hemoproteins were obtained. The electrochemical analysis of CYP3A4, CYP3A5, b5mc, b5om, b5(om-mc), and b5(mc-om) immobilized on screen printed graphite electrodes modified with membranous matrix revealed that these proteins have very close reduction potentials -0.435  -0.350 V (vs. Ag/AgCl). Cytochrome b5mc was shown to be capable of stimulating the electrocatalytic activity of CYP3A4 in the presence of its substrate testosterone.Issledovany mezhmolekuliarnye vzaimodeĭstviia mezhdu belkami-partnerami monooksigenaznoĭ sistemy biotransformatsii lekarstvennykh preparatov: tsitokhromami R450 3A4 i R450 3A5 i tsitokhromom b5. Tsitokhromy R450 3A4 i R450 3A5 obrazuiut kompleksy s kazhdoĭ iz form tsitokhroma b5 (mikrosomal'naia i mitokhondrial'naia formy - b5mc i b5om i dve “khimernye” konstruktsii b5(om-mc), b5(mc-om)), prichem sushchestvennoe razlichie nabliudalos' tol'ko vo vzaimodeĭstvii s b5om. Opredeleny élektroanaliticheskie kharakteristiki élektrodov s immobilizovannymi gemoproteinami: tsitokhromom R450 3A4, R450 3A5, b5mc, b5om, b5(om-mc) i b5(mc-om). Élektrokhimicheskiĭ analiz pokazal, chto vse éti belki obladaiut ochen' blizkimi redoks-potentsialami -0,435  -0,350 (otn. Ag/AgCl). V to zhe vremia, nabliudalos' stimuliruiushchee vliianie tsitokhroma b5mc na élektrokataliticheskie svoĭstva tsitokhroma R450 3A4.

Inflammatory diseases of the gut are associated with altered electrolyte and water transport, leading to the development of diarrhea. Epithelially expressed aquaporins (AQPs) are downregulated in inflammation, although the mechanisms involved are not known. We hypothesized that AQP3 expression in intestinal epithelial cells is altered in intestinal inflammation and that these changes are driven by tumor necrosis factor (TNF) α. Human colonic adenocarcinoma (HT‐29) cells were treated with TNF α to investigate signaling mechanisms in vitro. AQP3 expression was assessed by real‐time PCR and radiolabeled glycerol uptake, with select inhibitors and a luciferase reporter construct used to further elucidate intracellular signaling. AQP3 expression was downregulated in HT‐29 cells treated with TNF α. Luciferase reporter construct experiments revealed that TNF α downregulated constitutive transcriptional activity of the AQP3 promoter, and inhibition of MEK/ERK and nuclear factor κB (NF‐κB) signaling prevented the decrease in AQP3 mRNA expression. Constitutive AQP3 expression was suppressed by specificity protein (Sp) 3, and knockdown of this transcription factor bound to the AQP3 promoter was able to partially prevent the TNF α‐induced downregulation of AQP3. TNF α signals through MEK/ERK and NF‐κB to enhance the negative transcriptional control of AQP3 expression exerted by Sp3. Similar mechanisms regulate numerous ion channels, suggesting a common mechanism by which both ion and water transport are altered in inflammation.

© 2014 by The American Society for Biochemistry and Molecular Biology, Inc. Mucosal biopsies from inflamed colon of inflammatory bowel disease patients exhibit elevated epithelial apoptosis compared with those from healthy individuals, disrupting mucosal homeostasis and perpetuating disease. Therapies that decrease intestinal epithelial apoptosis may, therefore, ameliorate inflammatory bowel disease, but treatments that specifically target apoptotic pathways are lacking. Proteinase-activated receptor-2 (PAR2), a G protein-coupled receptor activated by trypsin-like serine proteinases, is expressed on intestinal epithelial cells and stimulates mitogenic pathways upon activation. We sought to determine whether PAR2 activation and signaling could rescue colonic epithelial (HT-29) cells from apoptosis induced by proapoptotic cytokines that are increased during inflammatory bowel disease. The PAR2 agonists 2-furoyl-LIGRLO (2f-LI), SLIGKV and trypsin all significantly reduced cleavage of caspase-3, -8, and -9, poly(ADP-ribose) polymerase, and the externalization of phosphatidylserine after treatment of cells with IFN-γ and TNF-α. Knockdown of PAR2 with siRNA eliminated the anti-apoptotic effect of 2f-LI and increased the sensitivity of HT-29 cells to cytokine-induced apoptosis. Concurrent inhibition of both MEK1/2 and PI3K was necessary to inhibit PAR2-induced survival. 2f-LI was found to increase phosphorylation and inactivation of pro-apoptotic BAD at Ser112 and Ser136 by MEK1/2 and PI3K-dependent signaling, respectively. PAR2 activation also increased the expression of anti-apoptotic MCL-1. Simultaneous knockdown of both BAD and MCL-1 had minimal effects on PAR2-induced survival, whereas single knockdown had no effect. We conclude that PAR2 activation reduces cytokine-induced epithelial apoptosis via concurrent stimulation of MEK1/2 and PI3K but little involvement of MCL-1 and BAD. Our findings represent a novel mechanism whereby serine proteinases facilitate epithelial cell survival and may be important in the context of colonic healing.

The prebiotic potential of nervine herbal medicines has been scarcely studied. We therefore used anaerobic human fecal cultivation to investigate whether medicinal herbs commonly used as treatment in neurological health and disease in Ayurveda and other traditional systems of medicine modulate gut microbiota. Profiling of fecal cultures supplemented with either Kapikacchu, Gotu Kola, Bacopa/Brahmi, Shankhapushpi, Boswellia/Frankincense, Jatamansi, Bhringaraj, Guduchi, Ashwagandha or Shatavari by 16S rRNA sequencing revealed profound changes in diverse taxa. Principal coordinate analysis highlights that each herb drives the formation of unique microbial communities predicted to display unique metabolic potential. The relative abundance of approximately one-third of the 243 enumerated species was altered by all herbs. Additional species were impacted in an herb-specific manner. In this study, we combine genome reconstruction of sugar utilization and short chain fatty acid (SCFA) pathways encoded in the genomes of 216 profiled taxa with monosaccharide composition analysis of each medicinal herb by quantitative mass spectrometry to enhance the interpretation of resulting microbial communities and discern potential drivers of microbiota restructuring. Collectively, our results indicate that gut microbiota engage in both protein and glycan catabolism, providing amino acid and sugar substrates that are consumed by fermentative species. We identified taxa that are efficient amino acid fermenters and those capable of both amino acid and sugar fermentation. Herb-induced microbial communities are predicted to alter the relative abundance of taxa encoding SCFA (butyrate and propionate) pathways. Co-occurrence network analyses identified a large number of taxa pairs in medicinal herb cultures. Some of these pairs displayed related culture growth relationships in replicate cultures highlighting potential functional interactions among medicinal herb-induced taxa.

Proteinase-activated receptor (PAR)2, a G protein-coupled receptor activated by serine proteinases, has been implicated in both intestinal inflammation and epithelial proliferation. Cyclooxygenase (COX)-2 is overexpressed in the gut during inflammation as well as in colon cancer. We hypothesized that PAR2 drives COX-2 expression in intestinal epithelial cells. Treatment of Caco-2 colon cancer cells with the PAR2-activating peptide 2-furoyl-LIGRLO-NH2 (2fLI), but not by its reverse-sequence PAR2-inactive peptide, for 3 h led to an increase in intracellular COX-2 protein expression accompanied by a COX-2-dependent increase in prostaglandin E2 production. 2fLI treatment for 30 min significantly increased metalloproteinase activity in the culture supernatant. Increased epidermal growth factor receptor (EGFR) phosphorylation was observed in cell lysates following 40 min of treatment with 2fLI. The broad-spectrum metalloproteinase inhibitor marimastat inhibited both COX-2 expression and EGFR phosphorylation. The EGFR tyrosine kinase inhibitor PD153035 also abolished 2fLI-induced COX-2 expression. Although PAR2 activation increased ERK MAPK phosphorylation, neither ERK pathway inhibitors nor a p38 MAPK inhibitor affected 2fLI-induced COX-2 expression. However, inhibition of either Src tyrosine kinase signaling by PP2, Rho kinase signaling by Y27632, or phosphatidylinositol 3 (PI3) kinase signaling by LY294002 prevented 2fLI-induced COX-2 expression. Trypsin increased COX-2 expression through PAR2 in Caco-2 cells and in an EGFR-dependent manner in the noncancerous intestinal epithelial cell-6 cell line. In conclusion, PAR2 activation drives COX-2 expression in Caco-2 cells via metalloproteinase-dependent EGFR transactivation and activation of Src, Rho, and PI3 kinase signaling. Our findings provide a mechanism whereby PAR2 can participate in the progression from chronic inflammation to cancer in the intestine.

A short biography and major scientific publications of Dmitri Dmitrievich Yablokov (1896-1993), member of the Russian Academy of Medical Sciences and an outstanding representative of the Tomsk therapeutic school, are presented.

76 patients with severe venous insufficiency (CVI) entered the study. All the patients received 500 mg of Detralex twice daily for 2 months. The drug was well tolerated and relieved CVI symptoms in the majority of cases.

The work analyzes the results of study of lipid metabolism in 53 patients who underwent operation for pancreatogenic peritonitis. The blood for the test was collected from the portal vein, the hepatic vein, and the aorta which made it possible to appraise metabolism in the liver according to the "entry-exit" blood flow system. It is shown that due to pancreatogenic toxemia, toxemic hepatocytic dyslipoproteinemia develops in patients with pancreonecrosis and persists in the late period. As a consequence of such a condition of lipid metabolism, early atherosclerotic damages to the arteries of the heart and brain and the peripheral arteries occur in patients after pancreonecrosis. The fate of patients was studied 8-10 years after the operation. The nature of atherosclerotic manifestations of toxemic hepatocytic dyslipoproteinemia in the late period after recovery from destructive pancreatitis was determined on the basis of study of central and peripheral hemodynamics.

The article analyses the efficacy of rehabilitation measures after implantation of a REPTELA cava-filter in 750 patients in the immediate postimplantation period and in 400 patients in late-term periods of up to 8 years. The average duration of the hospital stage of rehabilitation was 45 days for patients with thromboembolism of the pulmonary artery and 22 days for those without this condition. The application of a complex of rehabilitation measures makes it possible to restore the working capacity of 78.5% of patients with an implanted REPTELA cava-filter.

The article is based on study of the immediate results of REPTELA cava-filter implantation in 750 patients and the late-term results in 400 patients. The incidence of the complications is low. Hematoma at the site of subclavian vein puncture developed in 1.6%, retroperitoneal hematomas in 0.1%, migration of the cava-filter occurred in 0.9% of cases. The main causes of the complications are linked with improper methods of implantation of the cava-filter.

Experience in clinical application of the new antiembolic REPTELA cava-filter is generalized. The immediate (750 patients) and late-term results (400 patients) of implantation of the filter are discussed. Thromboembolism of the pulmonary artery was encountered in the postimplantation period in 1.2% of patients with 0.2% lethality. Technical faults of implantation were the causes of antiembolic inefficacy of the cava-filter.

The condition of the inferior vena cava system was studied in 597 patients after percutaneous implantation of the antiembolic cava-filter on the basis of the clinical findings and results of angiographic and pathoanatomical examination. The patency of the inferior vena cava was found to be maintained in the immediate postimplantation period in most patients. The causes of occlusion of the inferior vena cava in 10% of cases (according to the clinical findings) were embolic occlusion of the cava-filter and ascending thrombosis of the iliocaval segment.

The article is concerned with the methods used in the diagnosis of thromboembolism of the pulmonary artery. It is based on the experience in the examination of 160 patients admitted to the clinic with suspected pulmonary embolism, in 134 of whom the diagnosis was confirmed. The diagnostic possibilities of noncontrast X-ray examination of the lungs, electrocardio- and rheopneumography, catheterization of the heart and angiopneumography, and perfusion scan of the lungs are appraised.

Ultrasonic scanning was used in 115 patients with suspected occlusion of vena cava inferior. Details of ultrasonic diagnosis of non-occlusive and occlusive thrombosis of vena cava inferior and vena cava compression from the outside, monitoring of the thrombosed vena cava and the antiembolic cava filter are discussed.