Local effect of melatonin in an original dermal film limiting lipid peroxidation and accelerating healing in experimental thermal trauma

Разработка и патогенетическое обоснование новых подходов к локальной терапии термической травмы (ТТ) является актуальной и востребованной проблемой. В частности, представляет интерес разработка дермальных пленок (ДП), содержащих эндогенные регуляторы гомеостаза мультитропного действия. Цель исследования - оценка эффекта мелатонина (МТ) в составе оригинальной ДП на процессы репарации и содержание продуктов перекисного окисления липидов (ПОЛ) в коже очага повреждения при локальной термической травме. Методика. Эксперимент выполнен на 126 крысах-самцах Wistar. ТТ ІІІА степени площадью 3,5% моделировали погружением участка межлопаточной области кожи в очищенную воду с температурой 98-99 ºС на 12 с. МТ в составе ДП (0,005 г/г) на основе натрия карбоксиметилцеллюлозы наносили ежедневно после ТТ в течение 5 сут. На 5-е и 10-е сут после ТТ оценивали макроскопическую картину, площадь и глубину ожоговой раны, скорость ее эпителизации. Содержание продуктов ПОЛ в гомогенате кожи ожоговой раны определяли экстрационно-спектрофотометрическим методом в гептановой и изопропанольной фазах липидного экстракта. Результаты. Установлено, что накопление вторичных и конечных продуктов ПОЛ в гептановой и изопропанольной фазах липидного экстракта на 5-е и 10-е сут ассоциировано с площадью ожога. Применение оригинальной ДП с мелатонином приводит к снижению абсолютной и относительной площади ожога, увеличению скорости эпителизации ожоговой поверхности. На 5-е сут обнаружено снижение содержания вторичных и конечных продуктов ПОЛ в изопропанольной фазе, на 10-е сутки - снижение вторичных продуктов ПОЛ в гептановой фазе, конечных продуктов ПОЛ в изопропанольной фазе липидного экстракта. Заключение. Полученные результаты демонстрируют ускоряющий репарацию кожи в очаге ТТ эффект МТ в составе дермальной пленки за счет его ПОЛ-ограничивающего действия, расширяют представления о мультитропных эффектах МТ в организме и являются предпосылкой для применения ДП с МТ в клинической практике. Background. Development and pathogenetic justification of new approaches for local therapy of thermal trauma (TT) is a relevant and in-demand issue. Of special interest are dermal films (DF) containing endogenous pleiotropic regulators of homeostasis. Melatonin (MT) is one of such regulators that is suggested to be protective in TT. The aim of this study was to evaluate the effect of MT in the original DF on indexes of repair and concentration of lipid peroxidation (LPO) products in the injured skin after experimental TT. Methods. Experiments were performed on 126 Wistar male rats. Grade IIIA TT with an area of 3.5% was modeled by immersing a section of interscapular skin in purified water at a temperature of 98-99oC for 12 s. MT formulated into DF (0.005 g/g) based on sodium carboxymethylcellulose was applied after TT daily for 5 days. The macroscopic picture, area and depth of the burn wound, and the wound epithelization rate were evaluated on days 5 and 10 after TT. Concentration of LPO products in the injured skin homogenate was measured by extraction spectrophotometry in heptane and isopropanol phases of the lipid extract. Results. The accumulation of secondary and final LPO products in the heptane and isopropanol phases of the lipid extract on days 5 and 10 was associated with the burn area. The use of the original DF with MT resulted in a decrease in the absolute and relative areas of the burn and an increase in the rate of burn surface epithelialization. On day 5, a decrease in the content of secondary and final LPO products in the isopropanol phase was observed, and on day 10 decreases in secondary peroxidation products in the heptane phase and end LPO products in the isopropanol phase were detected. Conclusion. The results of this study demonstrated that MT formulated into DF accelerates skin repair in the TT focus due to its LPO-limiting effect, expands the understanding of MT pleiotropic effect, and represents a prerequisite for the clinical use of DF with MT.

Role of MIF -173G/C and Mbl2 codon 54A/B variants in risk of multiple myeloma: An association study

Background: Multiple myeloma (MM) is a malignant disease manifested by the clonal proliferation of atypical plasma cells. Macrophage inhibitory factor (MIF) is one of the pleiotropic regulators in various biological and cellular processes. Mannose-binding lectin (MBL) is a crucial protein involved in the lectin pathway of the immune system. Objective: We aimed to assess whether variants of MIF and MBL2 genes are associated with MM among a Turkish population. Methods: We analyzed the MIF-173G/C (rs755622) and MBL2 codon 54A/B (rs1800450) variants in 200 patients with MM and 200 healthy control subjects using a polymerase chain reaction (PCR) followed by restriction endonuclease digestion. There was also an evaluation of the patients undergoing autologous stem-cell transplantation (ASCT) for these variants. Results: AA and BB genotypes of MBL2 codon 54A/B increased in the patients as compared to the controls (p=0.008, p=0.001, respectively). The subjects carrying AA and BB genotypes of MBL2 were at high risk of development of susceptibility to MM by 7.377 and 8.812 times, respectively. The distribution of MBL2 codon 54A/B alleles was similar between the groups (p>0 .05). There was no statistical difference between the patients and controls in the genotype and allele frequencies of the MIF-173G/C variant (p>0 .05). The patients undergoing ASCT, MBL2 codon54A/B AA and BB genotypes also showed association with increased risk for MM (p=0.004, p=0.001, respectively). Conclusion: As far as we know, this is the first report of the study on an association between these variants and MM in our population. Our results indicate that the MBL2 codon 54A/B variant may be associated with susceptibility to MM.

Comparative Transcriptome Analysis of Streptomyces Clavuligerus in Response to Favorable and Restrictive Nutritional Conditions

Background: Clavulanic acid (CA), a β-lactamase inhibitor, is industrially produced by the fermentation of Streptomyces clavuligerus. The efficiency of CA production is associated with media composition, culture conditions and physiological and genetic strain characteristics. However, the molecular pathways that govern CA regulation in S. clavuligerus remain unknown. Methods and Results: Here we used RNA-seq to perform a comparative transcriptome analysis of S. clavuligerus ATCC 27064 wild-type strain grown in both a favorable soybean-based medium and in limited media conditions to further contribute to the understanding of S. clavuligerus metabolism and its regulation. A total of 350 genes were found to be differentially expressed between conditions; 245 genes were up-regulated in favorable conditions compared to unfavorable. Conclusion: The up-regulated expression of many regulatory and biosynthetic CA genes was positively associated with the favorable complex media condition along with pleiotropic regulators, including proteases and some genes whose biological function have not been previously reported. Knowledge from differences between transcriptomes from complex/defined media represents an advance in the understanding of regulatory paths involved in S. clavuligerus’ metabolic response, enabling the rational design of future experiments.

Genomic footprints of repeated evolution of CAM photosynthesis in tillandsioid bromeliads

The adaptive radiation of Bromeliaceae (pineapple family) is one of the most diverse among Neotropical flowering plants. Diversification in this group was facilitated by several ‘key innovations’ including the transition from C3 to CAM photosynthesis. We used a phylogenomic approach complemented by differential gene expression (RNA-seq) and targeted metabolite profiling to address the patterns and mechanisms of C3/CAM evolution in the extremely species-rich bromeliad genus Tillandsia and related taxa. Evolutionary analyses at a range of different levels (selection on protein-coding genes, gene duplication and loss, regulatory evolution) revealed three common themes driving the evolution of CAM: response to heat and drought, alterations to basic carbohydrate metabolism, and regulation of organic acid storage. At the level of genes and their products, CAM/C3 shifts were accompanied by gene expansion of a circadian regulator, re-programming of ABA-related gene expression, and adaptive sequence evolution of an enolase, effectively linking carbohydrate metabolism to ABA-mediated stress response. These changes include several pleiotropic regulators, which facilitated the evolution of correlated adaptive traits during a textbook adaptive radiation.