Svetlana Lyamina

Normobaric hypoxia conditioning reduces blood pressure and normalizes nitric oxide synthesis in patients with arterial hypertension.

Objectives Insufficient production and/or increased decomposition of the potent endogenous vasodilator nitric oxide plays an important role in development and progression of arterial hypertension and its complications. One of the most effective means of stimulating endogenous nitric oxide synthesis is controlled adaptation to hypoxia. This study examined the effect of a 20-day, intermittent, normobaric intermittent hypoxia conditioning (IHC) program on blood pressure (BP) and nitric oxide production in patients with stage 1 arterial hypertension. Methods The IHC sessions consisted of four to 10 cycles of alternating 3-min hypoxia (10% FIO2) and 3-min room air breathing. BP was monitored for 24 h before and after IHC, and nitric oxide synthesis was evaluated by 24-h urinary excretion of the stable nitric oxide metabolites nitrate and nitrite. Results IHC increased nitric oxide synthesis and decreased BP in hypertensive patients to values similar to those of normotensive individuals. Significant inverse correlations were found between nitric oxide production and disease duration, SBP, and DBP. Moreover, IHC enhancement of nitric oxide synthesis was especially robust in patients with arterial hypertension of more than 5 years duration. The reduction in BP persisted for at least 3 months in 28 of 33 hypertensive patients. Conclusion IHC exerted a robust, persistent therapeutic effect and can be considered as an alternative, nonpharmacological treatment for patients with stage 1 arterial hypertension. The antihypertensive action of IHC is associated with normalization of nitric oxide production.

Alternative Reprogramming of M1/M2 Phenotype of Mouse Peritoneal Macrophages In Vitro with Interferon-γ and Interleukin-4

An important role in the development of the immune response is played by macrophages that acquire either anti-inflammatory M1 or anti-inflammatory M2 phenotype depending on their microenvironment. The possibility of targeted reprogramming of the initial M2 macrophage phenotype towards M1 phenotype and vice versa using macrophage reprogramming factors IFN-γ and IL-4, respectively, was demonstrated. We showed that macrophages of genetically different mouse strains did not practically differ by their reprogramming capacity. Our findings suggest that macrophage programming not only participates in the triggering of the immune response, but also can ensure plasticity of functional activity during the developing response.

Macrophages Reprogrammed In Vitro Towards the M1 Phenotype and Activated with LPS Extend Lifespan of Mice with Ehrlich Ascites Carcinoma

Background The majority of tumors trigger macrophage reprogramming from an anti-tumor M1 phenotype towards a pro-tumor M2 phenotype. The M2 phenotype promotes tumor growth. We hypothesized that increasing the number of M1 macrophages in a tumor would limit carcinogenesis and extend the lifespan of the tumor host. The aim of this study was to verify this hypothesis in Ehrlich ascites carcinoma (EAC). The objectives were to evaluate effects of 1) EAC on a macrophage phenotype and NO-producing macrophage activity in vivo; 2) ascitic fluid from mice with EAC on a macrophage phenotype and NO-producing macrophage activity in vitro; and 3) in vitro reprogrammed M1 macrophages on lifespan of mice with EAC. Material/Methods The study was conducted using C57BL/6J mice. Results Concentration of nitrite, a stable NO metabolite and an index of NO production, was measured spectrophotometrically. Shifts of macrophage phenotype were assessed by changes in NO production as well as by amounts of CD80, a marker of M1 phenotype, and CD206, a marker of M2 phenotype. The CD markers were measured by flow cytometry. Macrophages were reprogrammed towards the M1 phenotype using two reprogramming factors: 0% FBS and 20 ng/ml IFN-γ. The study results showed that 1) EAC inhibited the macrophage NO production in vivo and reprogrammed macrophages towards the M2 phenotype; 2) ascitic fluid of mice with EAC inhibited the macrophage NO production in vitro and reprogrammed macrophages towards the M2 phenotype; and 3) injection of in vitro reprogrammed M1 macrophages into mice with EAC significantly increased the lifespan of mice. Conclusions These findings suggest that promising biotechnologies for restriction of tumor growth could be developed based on the in vitro macrophage reprogramming.

C57BL/6N Mice Are More Resistant to Ehrlich Ascites Tumors Than C57BL/6J Mice: The Role of Macrophage Nitric Oxide

Background Effectiveness of the immune defense formed by the genotype often determines the predisposition to cancer. Nitric oxide (NO) produced by macrophages is an important element in this defense. Material/Methods We hypothesized that genetic characteristics of NO generation systems can predetermine the vulnerability to tumor development. The study was conducted on mice of 2 genetic substrains – C57BL/6J and C57BL/6N – with Ehrlich ascites carcinoma (EAC). NO production in the tumor was changed using ITU, an iNOS inhibitor; c-PTIO, a NO scavenger; and SNP, a NO donor. Macrophage NO production was estimated by nitrite concentration in the culture medium. iNOS content was measured by Western blot analysis. Macrophage phenotype was determined by changes in NO production, iNOS level, and CD markers of the phenotype. Results The lifespan of C57BL/6N mice (n=10) with EAC was 25% longer (p<0.01) than in C57BL/6J mice (n=10). Decreased NO production 23% reduced the survival duration of C57BL/6N mice (p<0.05), which were more resistant to tumors. Elevated NO production 26% increased the survival duration of C57BL/6J mice (p<0.05), which were more susceptible to EAC. Both the NO production and the iNOS level were 1.5 times higher in C57BL/6N than in C57BL/6J mice (p<0.01). CD markers confirmed that C57BL/6N macrophages had the M1 and C57BL/6J macrophages had the M2 phenotype. Conclusions The vulnerability to the tumor development can be predetermined by genetic characteristics of the NO generation system in macrophages. The important role of NO in anti-EAC immunity should be taken into account in elaboration of new antitumor therapies.

M3 Macrophages Stop Division of Tumor Cells In Vitro and Extend Survival of Mice with Ehrlich Ascites Carcinoma

Background M1 macrophages target tumor cells. However, many tumors produce anti-inflammatory cytokines, which reprogram the anti-tumor M1 macrophages into the pro-tumor M2 macrophages. We have hypothesized that the problem of pro-tumor macrophage reprogramming could be solved by using a special M3 switch phenotype. The M3 macrophages, in contrast to the M1 macrophages, should respond to anti-inflammatory cytokines by increasing production of pro-inflammatory cytokines to retain its anti-tumor properties. Objectives of the study were to form an M3 switch phenotype in vitro and to evaluate the effect of M3 macrophages on growth of Ehrlich ascites carcinoma (EAC) in vitro and in vivo. Material/Methods Tumor growth was initiated by an intraperitoneal injection of EAC cells into C57BL/6J mice. Results 1) The M3 switch phenotype can be programed by activation of M1-reprogramming pathways with simultaneous inhibition of the M2 phenotype transcription factors, STAT3, STAT6, and/or SMAD3. 2) M3 macrophages exerted an anti-tumor effect both in vitro and in vivo, which was superior to anti-tumor effects of cisplatin or M1 macrophages. 3) The anti-tumor effect of M3 macrophages was due to their anti-proliferative effect. Conclusions Development of new biotechnologies for restriction of tumor growth using in vitro reprogrammed M3 macrophages is very promising.

Effects of Phenotype of Retinal Macrophages on the Features of Angiogenesis of Murine Retina

The period of forming of superficial vascular plexus during physiological retinal angiogenesis was shorter in C57Bl/6 mice. Experiments on the model of oxygen-induced retinopathy showed that avascular and vascularized zones in BALB/c mice on day 17 are smaller than in C57Bl/6 mice are by 5 and 1.5 times, respectively. The obtained results confirmed the importance of phenotype of retinal macrophages in the regulation of processes of both physiological and pathological retinal angiogenesis.

Changes in alveolar macrophage functional phenotype under an influence of age and genetic susceptibility as risk factors for chronic obstructive pulmonary disease

Хроническая обструктивная болезнь легких (ХОБЛ) вносит существенный вклад в повышение уровня инвалидизации населения и по прогнозам экспертов в самое ближайшее время займет 3 е место среди всех причин смерти [1]. В России в последние годы зарегистрировано от 2,4–11,0 млн больных ХОБЛ, а среди болезней органов дыхания ХОБЛ составля ет > 55 % [2, 3]. Особую роль в развитии и распро страненности ХОБЛ играет табакокурение [4]. По данным Всемирной организации здравоохранения, 73 % случаев смерти от ХОБЛ обусловлены именно курением [4]. ХОБЛ относится к мультикомпонентной систем ной патологии [5], в которой нарушение иммунного ответа в легких играет наиболее важную роль [6]. Развитие иммунного ответа предопределяется глав ными клетками врожденного иммунитета – макро фагами. Показано, что в зависимости от природы действующего патогена, модулирующих медиаторов и специфического микроокружения, макрофаги мо гут приобретать либо провоспалительный М1 фено тип, либо альтернативно – противовоспалительный М2 фенотип [6, 7]. По сравнению с М2 фенотипом, М1 макрофагами продуцируется большое количество провоспалитель ных цитокинов – интерлейкинов (IL) 12, фактора некроза опухоли α, NO и активных форм кислоро да [7], которыми и обусловлена бактерицидная актив ность макрофагов. Маркерами М1 являются повы шенная, по сравнению с М2 продукция NO, округлая форма макрофагов и поверхностно клеточные рецеп торы – рецептор IL 2 и МАРКО рецептор [7]. С.В.Лямина 1, Ш.Л.Шимшелашвили 1, Т.Ю.Веденикин 1, Е.В.Малышева 1, Н.П.Ларионов 2, И.Ю.Малышев 1, 3 Нарушение функционального фенотипа альвеолярных макрофагов при действии факторов риска хронической обструктивной болезни легких: возрастная и генетическая предрасположенность

Pressor response to 30-s breathhold: A predictor of masked hypertension

Abstract One in six adults has normal arterial blood pressure (BP) during a routine examination, but is hypertensive in other environments. This masked hypertension (MHT) may delay treatment until target organ damage has occurred. A sensitive, specific and economical test is needed to detect or exclude MHT in apparently normal subjects. The BP response to a 30-s breathhold (BH test) was observed in 269 young subjects with no evidence of cardiovascular disease. Of 226 normotensives (office BP ≤ 120/80), 25 (11%) had a positive BH test (test BP > 140/90 mmHg), and 12 (44%) of these subjects had MHT (positive 24-h ambulatory BP monitoring (BPM)). Of 201 subjects with negative BH test, none had MHT (negative BPM). Of 43 subjects with high normal BP (office BP > 120/80 < 140/90), 28 (65%) had a positive BH test and 22 of these subjects had MHT (positive BPM). Of the 15 subjects with high normal BP and with a negative BH test, none had MHT (negative BPM). Overall, the BH pressor test and BPM agreed in 93% of cases, and the BH test produced no false negative findings. The BH pressor test effectively ruled out MHT in normal subjects and accurately identified a population that should be further evaluated for MHT.