Regulatory effect of polyamines and indole on expression of stress adaptation genes in <i> Escherichia coli </i>

Background. Indole and polyamines are involved in the regulation of physiological processes in bacteria associated with adaptation to stress, biofilm formation, antibiotic tolerance, and bacterial persistence. However, the molecular targets and mechanisms of action of these metabolites are still poorly understood. In this work, we studied the effect of polyamines and indole on the expression of such genes as: rpoS, relA, and spoT, encoding regulators of the general stress responses and starvation; hns and stpA, encoding global regulators of gene expression; rmf, yqjD, hpf, raiA, rsfS, sra, ettA, encoding ribosome hibernation factors.The aim. To study the regulatory effects of polyamines and indole on the expression of these genes, which are responsible for the adaptation of Escherichia coli to stress.Materials and methods. We used strains of E. coli in this study. The amount of polyamines was studied by thin layer chromatography. The indole concentration was determined by high performance liquid chromatography. Gene expression was studied using real-time RT-PCR.Results. The addition of polyamines putrescine, cadaverine and spermidine to the medium stimulated the expression of all the studied genes. The maximal stimulation was observed at the stationary phase mostly. Putrescine and spermidine had the most significant effect. At 24 h of cultivation, an equimolar conversion of exogenous tryptophan into indole was showed. At this time, the expression of two genes – rmf and raiA – increased.Conclusions. We have shown that polyamines upregulate the expression of all the studied genes at the transcriptional level. The stimulating effect is specific for the phase of the batch culture and the type of polyamine. Indole has a positive effect on the expression of the rmf and raiA genes

Pain as one of the risk factors for progression of knee osteoarthrosis

Objective: to study the impact of pain intensity on the progression of knee osteoarthrosis (OA). Subjects and methods. One hundred and ten patients with knee OA were examined at a 5-year interval. All the patients underwent a questionnaire survey and knee joint pain assessment using a visual analog scale (VAS) and standard radiography. Results. After 5-year follow-up, radiographic OA progression was seen in 40 patients (Group 2); its stage remained the same in 70 patients (Group 1). In both groups, the patients were matched for age (59.2+9.5 and 59.0+8.1 years) and disease duration (11.1+10.6 and 13.7+9.9 years). During the first examination, pain on walking was more severe in Group 1 than in Group 2: 57.8+16.6 and 48.7+13.3 mm by VAS (р=0.002), as well as severe joint pain was predominant in these patients: 22.5 and 11.4%, respectively. Over the 5-year period, there was an increase in pain intensity. At the end of the follow-up, the patients with progressive OA rated their knee joint pain as severe in 35% of cases whereas in this index the non-progression group was only 12.9 (p = 0.012). Conclusion. In the OA progression group, pain intensity was initially statistically higher than that in the non-progression group. During 5-year follow-up, Group 1 showed an increase in knee joint pain intensity on walking, which can be considered as one of the predictors of gonarthrosis progression

Role of alarmone (p)ppGpp in the regulation of indole formation depending on glucose content in <i> Escherichia coli </i>

Signaling molecules such as indole (product of tryptophan catabolism) and (p)ppGpp (stringent response regulator) are involved in regulation of physiological processes in bacterial cells aimed to adapt to antibiotics and stresses. However, question of existence of relationship between the stringent response and indole signaling requires more detailed investigation.The aim. To study effect of stringent response regulator (p)ppGpp on indole production in Escherichia coli depending on glucose content.Materials and methods. In this work, we studied the dynamics of indole accumulation in batch cultures of parent E. coli BW25141 ((p)ppGpp+ strain) and deletion mutant BW25141∆relA∆spoT ((p)ppGpp0 strain) in glucose-mineral tryptophan-free M9 medium, as well as with 2 mM tryptophan addition. In order to study effect of starvation stress on bacterial cell ability to synthesize indole, we used a model of growth limitation by carbon substrate at two glucose concentrations, 0.1 % and 0.4 %.Results. We have shown here that (p)ppGpp absence in E. coli cells reduces their ability to produce indole in the tryptophan-free medium and significantly slows down the rate of its accumulation in the tryptophan-containing one. Low glucose concentration (0.1 %) leads to decrease in indole production by (p)ppGpp+ cells in the tryptophan-free medium. The presence of indole synthesis precursor, tryptophan, in growth medium, on the contrary, increases the production of indole at lower glucose concentration in both (p)ppGpp+ and (p)ppGpp0 strains demonstrating direct dependence of delay time for onset of indole formation on glucose content, which is more pronounced in the culture of deletion mutant unable of synthesizing (p) ppGpp. The data obtained can be interpreted as result of complex regulatory effect of catabolic repression and the stringent response caused by alarmone (p)ppGpp action on expression level of tnaCAB operon responsible for indole biosynthesis

Efficacy and safety of diacerein in patients with knee osteoarthritis

Diacerein (D) belongs to a class of symptomatic slow-acting agents, has an original mechanism of action, and is widely used as a diseasemodifying antirheumatic drug to treat osteoarthritis (OA) in Russia and many countries of the world. The ability of the drug to affect the main symptoms and progression of OA has been shown in a number of well-organized clinical trials.Objective: to evaluate the efficacy and safety of D in patients with knee OA.Patients and methods. An open-label trial evaluating the efficacy and safety of D (diaflex) in patients with knee OA was conducted in accordance with the multicenter program «Osteoarthrosis: Assessment of Progression in Real Clinical Practice». The trial included 80 patients of both sexes with Stage II–III knee OA; mean age, 60.8±6.8 years (47–75 years); mean body mass index, 31.8±5.9 kg/m2; disease duration, 10.3±5.7 years (2–30 years). The duration of the trial was 9 months (6 months of therapy and 3 months of follow-up).Results. There was a statistically significant reduction in visual analog scale pain on walking just 1 month after therapy initiation (57.1±9.7 and 44.7±13.9 mm; p&lt;0.0001) and a further significant improvement throughout the 6-month therapy. Pain did not increase after the drug was discontinued (the follow-up period was 3 months). The same pattern was observed in the assessment of the WOMAC index (pain during early therapy, 243.8±73.9; pain at the end of therapy, 137.5±78.9; stiffness, 97.8±41.1 and 57.7±38.6; functional failure, 875.8±250.4 and 525±305.7 respectively; p&lt;0.0001). Statistically significantly improved quality of life indicators measured by EQ-5D were noted throughout the follow-up period: 0.43±0.23 at the beginning of therapy, 0.61±0.14 at its end, and 0.63±0.11 at 3 months following treatment completion (p&lt;0.0001). By the time of therapy completion, 71.3% of the patients completely refused to take nonsteroidal anti-inflammatory drugs (NSAIDs). Both the patient and the physician evaluated the efficiency of treatment identically. By the end of therapy, 87.5% of the patients were observed to have improvement. Adverse reactions (ARs) were recorded in 10 (12.5%) patients and mainly associated with more frequent stools; ARs were not a cause of treatment interruptions or protocol deviations.Conclusion. Diaflex has a good symptomatic and anti-inflammatory effect: the therapy statistically significantly reduces pain, stiffness, and the need for NSAIDs and improves quality of life and joint function. The drug has a good safety profile and after-effects, which is seen at least 3 months after therapy discontinuation

Место нестероидных противовоспалительных препаратов в современных рекомендациях по остеоартриту

The paper provides a review of the data available in the literature on the relationship of pain to the risk of OA progression. Network analyses and numerous studies, including those conducted at the V.A. Nasonova Research Institute of Rheumatology, have confirmed that pain syndrome is one of the significant predictors of knee OA progression. The major class of medications for OA pain includes nonsteroidal anti-inflammatory drugs. The paper gives data on the efficacy of meloxicam in OA patients, which is widely used in both Russia and other countries of the world. Meloxicam is characterized by a good safety profile in the gastrointestinal tract, cardiovascular and renal systems. It is the drug of choice in patients with musculoskeletal diseases, in particular OA. Good results in severe pain syndrome have been shown by a step-by-step regimen of meloxicam when the injection formulation of the drug is used in the first days of treatment, and then, to consolidate what has been gained from therapy, its oral dosage form is administered in terms of concomitant diseases.В статье представлен обзор данных литературы, посвященный взаимосвязи боли и риска прогрессирования ОА. В сетевых анализах и многочисленных исследованиях, в том числе проведенных в ФГБНУ «Научно-исследовательский институт ревматологии им. В.А. Насоновой», подтверждено, что болевой синдром является одним из значимых предикторов прогрессирования ОА коленных суставов. К основному классу лекарственных средств для контроля боли при ОА относятся нестероидные противовоспалительные препараты (НПВП). Приведены данные об эффективности у пациентов с ОА мелоксикама, который широко применяется как в России, так и в других странах мира. Мелоксикам характеризуется хорошим профилем безопасности со стороны желудочно-кишечного тракта, сердечно-сосудистой и ренальной систем. Он является препаратом выбора у пациентов с заболеваниями костно-мышечной системы, в частности с ОА. При наличии выраженного болевого синдрома хорошо зарекомендовала себя ступенчатая схема назначения препарата, когда в первые дни лечения применяется инъекционная форма, а затем для закрепления терапевтического успеха – пероральная с учетом сопутствующих заболеваний

Симптоматические препараты замедленного действия (SYSADOA): новые возможности применения

The review systematizes modern data indicating effective pain control and a significant improvement in the functional activity of patients suffering from osteoarthritis (OA) using pharmaceutical substances of chondroitin sulfate (CS) and glucosamine (GA). The effect of a combination of CS and GA on subclinical inflammation (low-grade inflammation) in the joints, slowing down the progression of OA, reducing cardiovascular risk, metabolic disorders, etc. are discussed. There are promising reports of a possible decrease in overall mortality and mortality from cardiovascular diseases during long-term therapy with symptomatic delayed-acting drugs (SYSADOA). A wide range of pleiotropic effects of CS and HA allows us to classify these drugs as geroprotectors and recommend their use not only in OA, but also in various comorbid conditions.В обзоре систематизированы современные данные, свидетельствующие об эффективном контроле боли и значительном улучшении функциональной активности у пациентов с остеоартритом (ОА) на фоне применения фармацевтических субстанций хондроитина сульфата (ХС) и глюкозамина (ГА). Обсуждается влияние комбинации ХС и ГА на субклиническое воспаление (low-grade inflammation) в суставах, замедление прогрессирования ОА, уменьшение кардиоваскулярного риска, метаболических нарушений и др. Многообещающими представляются сообщения о возможном снижении общей летальности и смертности от сердечно-сосудистых заболеваний на фоне длительной терапии симптоматическими препаратами замедленного действия (SYSADOA). Широкий спектр плейотропных эффектов ХС и ГА позволяет отнести эти препараты к геропротекторам и рекомендовать их назначение не только при ОА, но и при различных коморбидных состояниях