Could the Propionic Acid Treatment in Combination with Metformin be Safe for the Small Intestine of Diabetic Rats?

BACKGROUND: Effects of propionic acid (PA) on the cellular and molecular processes in the small intestine under type 2 diabetes mellitus (T2DM)-induced endoplasmic reticulum (ER) stress remain incompletely studied. OBJECTIVES: The aim of the study was to assess the state of unfolded protein response (UPR) system in the small intestine of diabetic rats and to explore PA's influence on metformin treatment. METHODS: Male Wistar rats were divided into 1) control and 2) T2DM groups, and groups receiving (14 days, orally) 3) metformin (60 mg/kg), 4) PA (60 mg/kg), and 5) PA+metformin. Western blotting, RT-PCR, and transmission electron microscopy were performed. RESULTS: We found that T2DM induced elevation of ER intermembrane space and UPR overactivation based on increased GRP78, ATF6 and PERK levels in small intestine. Metformin treatment led to a further UPR activation. PA supplementation partially restored enterocytes functioning via normalization of ATF6 and PERK content, while IRE1 level reached the maximum value, compared to all groups. The most pronounced effect of adaptation to the T2DMinduced ER stress was observed after combined metformin and PA action. In particular, decreased ER intermembrane space in enterocytes was detected compared to separate metformin and PA administration, which was accompanied by restored GRP78, PERK and IRE1 levels. CONCLUSION: Our study proves the safety of additional therapy with propionic acid in combination with metformin for the functional state of small intestine. Due to its ability to modulate UPR signaling, PA may be considered a safe and perspective candidate for supportive therapy in T2DM, especially for neuroprotection.

Key success factors for the implementation of quality management systems in developing countries.

Background: Despite the tremendous progress made in advancing laboratory medicine in low- and middle-income countries (LMICs), inadequate quality management systems (QMSs) remain a problem and barrier to provision of reliable laboratory services in resource-limited settings. Therefore, it is useful to study the experience of medical laboratories in LMICs that have successfully implemented QMS. Aim: This review identified key success factors (KSFs) for medical laboratories in LMICs implementing QMS in accordance with the International Organization for Standardization standard 15189 as a pathway to improving laboratory quality. Methods: Applying Preferred Reporting Items for Systematic Reviews procedures, we conducted a targeted search of studies from LMICs published between 2012 and 2022 to identify KSFs. Thirty-two out of 952 references retrieved were considered relevant and included in this review. Grounded theory was used to extract key features of the included studies to derive KSFs. Results: Ten KSFs for medical laboratories striving to implement QMS were identified and described. These KSFs were integrated to create a model of success for laboratory QMS implementation. The model consists of three underlying factors, namely preparing for change, resource availability, and effective project management, each comprising three separate KSFs. Institutional commitment was identified as the core of the model and is integral to ensuring the quality of laboratory services. Conclusion: Laboratories planning to implement a QMS can benefit from understanding the KSFs demonstrated in this study as this would help them to identify the necessary changes to implement and set realistic expectations about the outcomes of QMS implementation.

Regulation of the apoptosis/autophagy switch by propionic acid in ventromedial hypothalamus of rats with type 2 diabetes mellitus.

Background: Hypothalamic dysregulation may cause abnormal glucose metabolism and type 2 diabetes mellitus (T2DM). The balance between autophagy and apoptosis is important for maintaining cellular/tissue homeostasis and may be disrupted in T2DM. Objectives: Since propionic acid (PA) exerts neuroprotective effects, the aim was to investigate its effects on apoptosis/autophagy switch in the ventromedial hypothalamus (VMH) of T2DM rats. Materials and methods: Male Wistar rats were divided: 1) control; 2) T2DM; groups that received (14 days, orally): 3) metformin (60 mg/kg); 4) sodium salt of PA (60 mg/kg); 5) PA + metformin. Western blotting (Bax, Bcl-xl, LC3, Beclin-1, caspase-3), RT-PCR (Bax, Bcl-xl, LC3, Beclin-1), transmission electron microscopy and immunohistochemical staining (Bax, Bcl-xl) were performed on the VMH samples. Results: T2DM-induced apoptosis and mitoptosis, enlarged endoplasmic reticulum (ER) tubules/cisterns were observed in VMH, and accompanied by an imbalance of pro- and anti-apoptotic factors: elevation of pro-apoptotic markers Bax and caspase-3, decrease in autophagy protein LC3 and anti-apoptotic Bcl-xl. Metformin and PA administration partially improved VMH ultrastructural changes by reducing mitochondrial swelling and diminishing the number of apoptotic neurons. Metformin inhibited neuronal apoptosis, however, caused reactive astrogliosis and accumulation of lipofuscin granules. Elevated number of autophagosomes was associated with the LC3, Beclin-1 and Bcl-xl increase and decrease in Bax and caspase-3 vs. T2DM. PA switched cell fate from apoptosis to autophagy by elevating LC3 and Beclin-1 levels, increasing Bcl-xl content that altogether may represent adaptive response to T2DM-induced apoptosis. PA + metformin administration lowered relative area of ER membranes/cisterns vs. control, T2DM and metformin, and was optimal considering ratio between the pro-apoptotic, anti-apoptotic and autophagy markers. Conclusion: T2DM was associated with apoptosis activation leading to impairments in VMH. PA in combination with metformin may be effective against diabetes-induced cell death by switching apoptosis to autophagy in VMH.

Plasma-derived exosomes implement miR-126-associated regulation of cytokines secretion in PBMCs of CHF patients in vitro.

Background The investigation of regulatory effects of intra-exosomal compounds, especially microRNAs, has promising therapeutic prospects in the treatment of numerous diseases, including cardiovascular disorders. In this study, we investigated the effect of healthy donors` plasma exosomes (HDPE) on the production of cytokines by PBMC cells of patients with congestive heart failure (CHF) and showed the integral role of miRNA-126 in CHF-mediated changes of mononuclear paracrine secretion. Methods Peripheral blood mononuclear cells (PBMСs) were isolated from a peripheral blood of fifteen patients with CHF (age, 66,8±9,8 years; left ventricular ejection fraction, 44±19%). The concentration of cytokines (IL-10, ICAM-1, VEGF-A, TNF-α and MCP-1) in culture medium and PBMCs was measured by ELISA. The level of miRNA-126 expression in PBMCs was performed by real-time PCR. Results Dramatic increase of ICAM-1 level in activated PBMCs of CHF patients, as well as an increase of the IL-10, ICAM-1 and TNF-α levels in the culture medium was observed. It was accompanied by CHF-related miRNA-126 overexpression in PBMCs. HDPE treatment distinguished by a tendency to reduction in miRNA-126 expression by CHF PBMCs and correlated with upregulation of IL-10, ICAM-1, TNF-α and MCP-1 with normalization of cytokines secretion. Conclusions The altered paracrine secretion of cytokines by CHF PBMCs and miRNA-126 overexpression in vitro was found. HDPE treatment modulated production and secretion of most of studied cytokines by CHF PBMCs in vitro. The experimental application of exosomes for the modulation of paracrine secretion and PBMCs cellular functions may be promising for CVD therapy, including endothelial dysfunction and CHF.

THE EFFECT OF NOS3 AND AGTR1 GENOTYPES ON THE COURSE OF THE ARTERIAL HYPERTENSION FOR THE OVERWEIGHT OR OBESE PATIENTS.

OBJECTIVE: The aim: Objective of the research is to determine the effect of NOS3 and AGTR1 genotypes of patients with arterial hypertension and high body mass index in the course of the disease. PATIENTS AND METHODS: Materials and methods: 58 patients (22 men and 36 women) with AH and high BMI were examined. The average age of the examined patients was 53.6±8.7 years. The analysis of rs1799983 polymorphisms of the NOS3 gene (localization 7q36.1; 7:150999023) and AGTR1 (type 1 receptor for angiotensin 2 1166 A>C) was performed using TaqMan assay (Thermo Fisher Scientific, USA) by real-time PCR (Applied Biosystems, USA) using TaqMan probe amplification products. Genomic DNA samples were isolated from stabilized blood using a Genomic DNA Mini Kit reagent (Invitrogen, USA). The Statistica 10 program (StatSoft Inc.) was used for statistical processing of the obtained data, USA). The independent samples were compared using the Mann-Whitney (U) criterion. In all cases of statistical evaluation, the reliability of differences was taken into account at a value of p<0.05. CONCLUSION: Results and conclusions: Polymorphism of the NOS3 and AGTR1 genes is associated with early development and complicated course of cardiovascular pathology. The combination of NOS3 and AGTR1 gene polymorphism in patients with the high body mass index increases the risk of complications in hypertension. Using a mathematical model to predict the probability (95%) of genetic mutations in two genes (NOS3 and AGTR1) increases the effectiveness of diagnosis for patients with the high risk of developing cardiovascular complications.

Effect of Propionic Acid on Diabetes-Induced Impairment of Unfolded Protein Response Signaling and Astrocyte/Microglia Crosstalk in Rat Ventromedial Nucleus of the Hypothalamus.

Background: The aim was to investigate the influence of propionic acid (PA) on the endoplasmic reticulum (ER), unfolded protein response (UPR) state, and astrocyte/microglia markers in rat ventromedial hypothalamus (VMH) after type 2 diabetes mellitus (T2DM). Methods: Male Wistar rats were divided: (1) control, (2) T2DM, and groups that received the following (14 days, orally): (3) metformin (60 mg/kg), (4) PA (60 mg/kg), and (5) PA+metformin. Western blotting, RT-PCR, transmission electron microscopy, and immunohistochemical staining were performed. Results: We found T2DM-associated enlargement of ER cisterns, while drug administration slightly improved VMH ultrastructural signs of damage. GRP78 level was 2.1-fold lower in T2DM vs. control. Metformin restored GRP78 to control, while PA increased it by 2.56-fold and metformin+PA-by 3.28-fold vs. T2DM. PERK was elevated by 3.61-fold in T2DM, after metformin-by 4.98-fold, PA-5.64-fold, and metformin+PA-3.01-fold vs. control. A 2.45-fold increase in ATF6 was observed in T2DM. Metformin decreased ATF6 content vs. T2DM. Interestingly, PA exerted a more pronounced lowering effect on ATF6, while combined treatment restored ATF6 to control. IRE1 increased in T2DM (2.4-fold), metformin (1.99-fold), and PA (1.45-fold) groups vs. control, while metformin+PA fully normalized its content. The Iba1 level was upregulated in T2DM (5.44-fold) and metformin groups (6.88-fold). Despite PA treatment leading to a further 8.9-fold Iba1 elevation, PA+metformin caused the Iba1 decline vs. metformin and PA treatment. GFAP level did not change in T2DM but rose in metformin and PA groups vs. control. PA+metformin administration diminished GFAP vs. PA. T2DM-induced changes were associated with dramatically decreased ZO-1 levels, while PA treatment increased it almost to control values. Conclusions: T2DM-induced UPR imbalance, activation of microglia, and impairments in cell integrity may trigger VMH dysfunction. Drug administration slightly improved ultrastructural changes in VMH, normalized UPR, and caused an astrocyte activation. PA and metformin exerted beneficial effects for counteracting diabetes-induced ER stress in VMH.

THE EFFECTIVENESS OF THERAPY BY CRYOPRESERVED HUMAN PLASMA IN PATIENTS WITH DEFICIENCY OF MANNOSE BINDING LECTIN SUFFERING FROM HERPES VIRUS INFECTION.

OBJECTIVE: The aim: To research the ef f ectiveness of cryopreserved blood plasma replacement therapy in patients with primary mannose binding lectin (MBL) def i ciency, suf f ering from chronic active herpes virus infections. PATIENTS AND METHODS: Materials and methods: Patients of the study group (SG) n= 36 additionally received cryopreserved blood plasma therapy Octaplas (Octapharma, Switzerland). Patients of the control group (CG) n=36 received only chemotherapy with Valganciclovir 450 mg 2/day per os for 1-3 months. The diagnosis of active herpes virus infection was established by PCR of blood leukocytes. Statistical analysis of the obtained information was processed by the calculation of the chi-square (χ2) Pearson criterion, the odds ratio and the associated 95% conf i dence interval (95% CI). RESULTS: Results: The adding cryopreserved blood plasma substitute to standard therapy with valganciclovir for the treatment of chronic active herpes virus infection in patients with total serum MBL def i ciency below 50 ng/ml, allowed to get more negative PCR results. The ef f ectiveness of combination therapy was 50% higher in carrier of HHV-6 (χ2=8,533 and р=0,004; Yeats correction 6,533 and signif i cance 0,011; OR=11,667 and 95% CI=1,939-70,180) and 43% in carrier of HHV-7 (χ2=8,846 and р=0,003; Yeats correction 7,165 and signif i cance 0,008; OR=6,375 and 95% CI=1,711-23,758), compared with monotherapy. The close association between def i cit MBL compensation and the results of antiviral treatment is also reported. The ef f ect of such treatment in patients with chronic EBV infection was less (27%). CONCLUSION: Conclusions: We assumed, that virostatic ef f ect of valganciclovir is increased by MBL-mediated clearance of blood serum from viral particles.

Correlational analysis of the regulatory interplay between molecules and cellular components mediating angiogenesis in wound healing under normal and hyperglycemic conditions.

AIM: The aim of this study was to correlate the content of cells with regulatory molecules associated with angiogenesis in wound healing in a rat model of hyperglycemia. We hypothesize that blood neutrophils are the main VEGF source and can stimulate FLT-1 receptor expression, which is the perquisite for efficient neoangiogenesis. MATERIALS AND METHODS: Kinetic studies of the healing dynamics (3, 7, 14, 21 days) of burn wounds on the skin were conducted in white adult male rats. The content of nuclear factor kappa B (NF-κB), vascular endothelial growth factor (VEGF), its receptor (Flt-1) in the regenerated tissue was analyzed by western blot. Numbers of cells associated with the regenerative process and from peripheral blood (PB) were determined. Additionally a bone marrow (BM) myelogram was conducted. RESULTS: The relative number of peripheral blood (PB) neutrophils was found to be associated with the level of VEGF (R = 0.708) and Flt-1 (R = 0.472). The relative number of fibroblasts was also associated with VEGF (R = 0.562), but not with Flt-1. A negative association was found between the number of neutrophils in the regenerated tissue with VEGF (R = -0.454) and FLT-1 (R = -0.665). This confirms our hypothesis, that blood neutrophils are the main VEGF producer that stimulate the expression of the FLT-1 receptor subsequently inducing neoangiogenesis.Furthermore, that under hyperglycemic conditions fibroblasts were highly associated with VEGF (R = 0.800), while negatively associated with FLT-1 (R = -0.506). There was a high association between PB neutrophils and newly generated tissue cells: neutrophils (R = 0.717) and macrophages (R = 0.622), as well as the association between neutrophils and macrophages (R = 0.798). This is an indication of chronic inflammation and increased transmigration of blood cells to the burned tissue. CONCLUSION: Blood neutrophils are the main producer of VEGF and stimulate the expression of the FLT-1 receptor. In the context of hyperglycemia the imbalance of receptor and ligand associated with angiogenesis indicates for chronic inflammation: VEGF and FLT-1, which facilitates hypoxia, prevents the physiological course of burn wound healing and may be an important factor in impaired tissue regeneration in diabetes.

Robust hepatitis B vaccine-reactive T cell responses in failed humoral immunity.

While virus-specific antibodies are broadly recognized as correlates of protection, virus-specific T cells are important for direct clearance of infected cells. Failure to generate hepatitis B virus (HBV)-specific antibodies is well-known in patients with end-stage renal disease. However, whether and to what extent HBV-specific cellular immunity is altered in this population and how it influences humoral immunity is not clear. To address it, we analyzed HBV-reactive T cells and antibodies in hemodialysis patients post vaccination. 29 hemodialysis patients and 10 healthy controls were enrolled in a cross-sectional study. Using multiparameter flow cytometry, HBV-reactive T cells were analyzed and functionally dissected based on granzyme B, interferon-γ (IFN-γ), tumor necrosis factor alpha (TNF-α), interleukin-2 (IL-2), and IL-4 expression. Importantly, HBV-reactive CD4+ T cells were detected not only in all patients with sufficient titers but also in 70% of non-responders. Furthermore, a correlation between the magnitude of HBV-reactive CD4+ T cells and post-vaccination titers was observed. In summary, our data showed that HBV-reactive polyfunctional T cells were present in the majority of hemodialysis patients even if humoral immunity failed. Further studies are required to confirm their in vivo antiviral capacity. The ability to induce vaccine-reactive T cells paves new ways for improved vaccination and therapy protocols.

The regulatory role of the RANKL/RANK/OPG signaling pathway in the mechanisms of tooth eruption in patients with impacted teeth.

BACKGROUND: Tooth impaction is a common problem in orthodontic practice and in some cases accompanied by pain and pathological changes of surrounding teeth. Understanding the cellular and molecular mechanisms underlying tooth impaction allows finding the most effective orthodontic treatment for patients with impacted teeth (IT). RANK (receptor activator of NF-κB) / RANKL (RANK ligand) / OPG (osteoprotegerin) signaling pathway controls bone resorption and may be involved in the regulation of tooth eruption. The study aimed to evaluate bone remodeling based on the assessment of the RANKL/RANK/OPG status in patients with IT. METHODS: Bone samples from 18 patients (mean age 25.27 ± 3.34) were divided into 3 groups: 1 - bone tissue of healthy persons (control group); 2 - bone tissue, that was taken near the healthy tooth in patients with tooth impaction; 3 - bone tissue, that was collected near the IT. Levels of RANKL, RANK, OPG, osteocalcin (OC), NF-κB p65 subunit, NFATc1, and caspase-3 were determined by western blotting. The difference between groups was assessed using ANOVA followed by Tukey's post-hoc test. P-value ≤0.05 was considered statistically significant. RESULTS: We established a 1.73-fold elevation of RANK level in the IT area vs. control, indicating the recruitment of preosteoclasts. An increase in RANKL, OPG, and OC content was demonstrated (1.46-, 1.48-, and 1.42-fold respectively), reflecting the high activity of osteoblasts near the IT. Despite the activation of the RANKL/RANK/OPG system in the impaction area, NF-κB and NFATc1 levels did not change compared vs. control, indicating a blocked/delayed process of osteoclastogenesis. We found a decrease in the content of procaspase-3 (1.28-fold), while the level of its active form p17 increased by 2.26 folds near the healthy tooth in patients with IT compared with control. In the area of ​​IT, we observed an increase in procaspase-3 and p17 levels (1.32 and 1.78 folds). This reflects impairments of caspase-3 activation and accumulation of its inactive form in the IT area that may contribute to the tooth eruption failure. CONCLUSIONS: Tooth impaction may be associated with the disturbances in the caspase-3 cascade activation and the imbalance in the RANKL/RANK/OPG system, and as a result, blocked bone resorption.