Mesenchymal stem cells attenuate liver fibrosis by suppressing Th17 cells - an experimental study.

This study investigates molecular and cellular mechanisms involved in mesenchymal stem cell (MSC)-mediated modulation of IL-17 signaling during liver fibrosis. Mice received CCl4 (1 µl/g intraperitoneally) twice/week for 1 month. MSCs (1 × 106 ), or MSC-conditioned medium (MSC-CM), were intravenously injected 24 h after CCl4 and on every 7th day. Liver fibrosis was determined by macroscopic examination, histological analysis, Sirius red staining, and RT-PCR. Serum levels of cytokines, indoleamine 2,3-dioxygenase (IDO), and kynurenine were determined by ELISA. Flow cytometry was performed to identify liver-infiltrated cells. In vitro, CD4+ T cells were stimulated and cultured with MSCs. 1-methyltryptophan was used for inhibition of IDO. MSCs significantly attenuated CCl4 -induced liver fibrosis by decreasing serum levels of inflammatory IL-17, increasing immunosuppressive IL-10, IDO, and kynurenine, reducing number of IL-17 producing Th17 cells, and increasing percentage of CD4+ IL-10+ T cells. Injection of MSC-CM resulted with attenuated fibrosis accompanied with the reduced number of Th17 cells in the liver and decreased serum levels of IL-17. MSC-CM promoted expansion of CD4+ FoxP3+ IL-10+ T regulatory cells and suppressed proliferation of Th17 cells. This phenomenon was completely abrogated in the presence of IDO inhibitor. MSCs, in IDO-dependent manner, suppress liver Th17 cells which lead to the attenuation of liver fibrosis.

Mesenchymal stem cells attenuate acute liver injury by altering ratio between interleukin 17 producing and regulatory natural killer T cells.

Mesenchymal stem cells (MSCs) are, due to immunomodulatory characteristics, considered as novel agents in the treatment of immune-mediated acute liver failure. Although it is known that MSCs can regulate activation of T lymphocytes, their capacity to modulate function of neutrophils and natural killer T (NKT) cells, major interleukin (IL) 17-producing cells in acute liver injury, is still unknown. By using 2 well-established murine models of neutrophil and NKT cell-mediated acute liver failure (induced by carbon tetrachloride and α-galactoceramide), we investigated molecular and cellular mechanisms involved in MSC-mediated modulation of IL17 signaling during acute liver injury. Single intravenous injection of MSCs attenuate acute hepatitis and hepatotoxicity of NKT cells in a paracrine, indoleamine 2,3-dioxygenase (IDO)-dependent manner. Decreased levels of inflammatory IL17 and increased levels of immunosuppressive IL10 in serum, reduced number of interleukin 17-producing natural killer T (NKT17) cells, and increased presence of forkhead box P3 + IL10-producing natural killer T regulatory cells (NKTregs) were noticed in the injured livers of MSC-treated mice. MSCs did not significantly alter the total number of IL17-producing neutrophils, CD4+, and CD8 + T lymphocytes in the injured livers. Injection of mesenchymal stem cell-conditioned medium (MSC-CM) resulted with an increased NKTreg/NKT17 ratio in the liver and attenuated hepatitis in vivo and significantly reduced hepatotoxicity of NKT cells in vitro. This phenomenon was completely abrogated in the presence of IDO inhibitor, 1-methyltryptophan. In conclusion, the capacity of MSCs to alter NKT17/NKTreg ratio and suppress hepatotoxicity of NKT cells in an IDO-dependent manner may be used as a new therapeutic approach in IL17-driven liver inflammation. Liver Transplantation 23 1040-1050 2017 AASLD.

Combined effects of electromagnetic field and low-level laser increase proliferation and alter the morphology of human adipose tissue-derived mesenchymal stem cells.

In recent years, electromagnetic field (EMF) and low-level laser (LLL) have been found to affect various biological processes, the growth and proliferation of cells, and especially that of stem cells. The aim of this study was to investigate the effects of EMF and LLL on proliferation of human adipose tissue-derived mesenchymal stem cells (hAT-MSCs) and thus to examine the impact of these therapeutic physical modalities on stem cell engraftment. hAT-MSCs were isolated from subcutaneous adipose tissue of six persons ranging in age from 21 to 56 years. EMF was applied for a period of 7 days, once a day for 30 min, via a magnetic cushion surface at a frequency of 50 Hz and an intensity of 3 mT. LLL was applied also for 7 days, once a day for 5 min, at radiation energies of 3 J/cm2, with a wavelength of 808 nm, power output of 200 mW, and power density of 0.2 W/cm2. Nonexposed cells (control) were cultivated under the same culture conditions. Seven days after treatment, the cells were examined for cell viability, proliferation, and morphology. We found that after 7 days, the number of EMF-treated hAT-MSCs was significantly higher than the number of the untreated cells, LLL-treated hAT-MSCs were more numerous than EMF-treated cells, and hAT-MSCs that were treated with the combination of EMF and LLL were the most numerous. EMF and/or LLL treatment did not significantly affect hAT-MSC viability by itself. Changes in cell morphology were also observed, in terms of an increase in cell surface area and fractal dimension in hAT-MSCs treated with EMF and the combination of EMF and LLL. In conclusion, EMF and/or LLL treatment accelerated the proliferation of hAT-MSCs without compromising their viability, and therefore, they may be used in stem cell tissue engineering.

Comparative analysis of the effects combined physical procedures and alpha-lipoic acid on the electroneurographic parameters of patients with distal sensorimotor diabetic polyneuropathy.

[Purpose] Painful diabetic polyneuropathy occurs as a complication in 16% of all patients with diabetes mellitus. [Subjects and Methods] A clinical, prospective open-label randomized intervention study was conducted of 60 adult patients, with distal sensorimotor diabetic neuropathy two groups of 30 patients, with diabetes mellitus type 2 with distal sensorimotor diabetic neuropathy. Patients in group A were treated with combined physical procedures, and patients in group B were treated with alpha lipoic acid. [Results] There where a statistically significant improvements in terminal latency and the amplitude of the action potential in group A patients, while group B patients showed a statistically significant improvements in conduction velocity and terminal latency of n. peroneus. Group A patients showed a statistically significant improvements in conduction velocity and terminal latency, while group B patients also showed a statistically significant improvements in conduction velocity and terminal latency. This was reflected in a significant improvements in electrophysiological parameters (conduction velocity, amplitude and latency) of the motor and sensory nerves (n. peroneus, n. suralis). [Conclusion] These results present further evidence justifying of the use of physical agents in the treatment of diabetic sensorimotor polyneuropathy.

Mesenchymal stem cells in regenerative rehabilitation.

[Purpose] Regenerative medicine and rehabilitation contribute in many ways to a specific plan of care based on a patient's medical status. The intrinsic self-renewing, multipotent, regenerative, and immunosuppressive properties of mesenchymal stem cells offer great promise in the treatment of numerous autoimmune, degenerative, and graft-versus-host diseases, as well as tissue injuries. As such, mesenchymal stem cells represent a therapeutic fortune in regenerative medicine. The aim of this review is to discuss possibilities, limitations, and future clinical applications of mesenchymal stem cells. [Subjects and Methods] The authors have identified and discussed clinically and scientifically relevant articles from PubMed that have met the inclusion criteria. [Results] Direct treatment of muscle injuries, stroke, damaged peripheral nerves, and cartilage with mesenchymal stem cells has been demonstrated to be effective, with synergies seen between cellular and physical therapies. Over the past few years, several researchers, including us, have shown that there are certain limitations in the use of mesenchymal stem cells. Aging and spontaneous malignant transformation of mesenchymal stem cells significantly affect the functionality of these cells. [Conclusion] Definitive conclusions cannot be made by these studies because limited numbers of patients were included. Studies clarifying these results are expected in the near future.

Treatment of trochanteric bursitis: our experience.

[Purpose] Trochanteric bursitis is a disease for which there are no effective standardized therapy protocols. Very often pain persists in spite of applying all therapeutic treatments. The purpose of this study was to determine whether treatment of trochanteric bursitis with a local injection of bicomponent corticosteroid and 2% lidocaine would improve patients' conditions and relieve pain symptoms in the trochanteric area. [Subjects and Methods] A retrospective observational study was conducted of 2,217 patients in a 6 year follow-up period at the Special Hospital "Agens", Mataruska Banja, Serbia. [Results] Of 2,217 examined patients, 58 (2.6%) patients were found to suffer from trochanteritis associated with low back pain, and 157 (7%) were found to suffer from trochanteric pains without low back pains. Local corticosteroid therapy followed by physical therapy was effective in 77 (49%) of these patients, and only corticosteroid injection in 61 (39%) patients. A single injection was given to 47 (29.9%) of the patients. Two injections were given to 9 (5.7%) patients, and from 3 to 5 injections were given repeatedly every 4-6 weeks to 7 (4.5%) patients. [Conclusion] For most patients, local injections of corticosteroids with lidocaine alone or followed by physical therapy gave satisfactory results.

Concise review: Therapeutic potential of mesenchymal stem cells for the treatment of acute liver failure and cirrhosis.

Currently, the most effective therapy for acute liver failure and advanced cirrhosis is liver transplantation. However, this procedure has several limitations, including lack of donors, surgical complications, immunological suppression, and high medical costs. The alternative approaches that circumvent the use of a whole liver, such as stem cell transplantation, have been suggested as an effective alternate therapy for hepatic diseases. Mesenchymal stem cells (MSCs), also known as multipotent mesenchymal stromal cells, are self-renewing cells that can be found in almost all postnatal organs and tissues, including liver. During the past decade, great progress has been made in the field of MSC-dependent liver regeneration and immunomodulation. Because of their potential for differentiation into hepatocytes as well as their immunomodulatory characteristics, MSCs are considered as promising therapeutic agents for the therapy of acute liver failure and cirrhosis. In this concise review, we have summarized therapeutic potential of MSCs in the treatment of acute liver failure and cirrhosis, emphasizing their regenerative and immunomodulatory characteristics after engraftment in the liver. We have also presented several outstanding problems including conflicting data regarding MSCs engraftment in the liver and unwanted mesenchymal lineage differentiation in vivo which limits MSC therapy as a mainstream treatment approach for liver regeneration. It can be concluded that efficient and safe MSC-based therapy for acute and chronic liver failure remains a challenging issue that requires more investigation and continuous cooperation between clinicians, researchers, and patients.

COVID-19 Death in Novi Pazar - "Serbian Bergamo".

Serbia was one of the countries in Europe and the world that were most affected by the coronavirus disease 2019 (COVID-19) pandemic. City Novi Pazar was the greatest coronavirus hotspot in Europe on July 1, 2020, due to several hundred infected people. Even though united data were published at the state level, there are no data by region or city, so the interpretation of the COVID-19 epidemic in Serbia at the regional level is difficult. Different levels of health care and health education of citizens and the degree of respect for the proposed epidemiological measures have led to significant differences in the number of tests, a large number of infected, and several deaths by regions and cities. Insufficiently precise and up-to-date keeping of records and statistical data on COVID-19 at the state and local level also complicates the pandemic's scientific and epidemiological analysis. Novi Pazar is a city in southwestern Serbia with a population of 100,000. It is similar in population to the city of Bergamo, in northern Italy in the Lombardy region. As of July 1, 2020, Novi Pazar had 300% higher mortality per 100,000 population compared with the same month last year, and almost 10 times higher mortality than the rest of Serbia.

Corneal Stem Cells as a Source of Regenerative Cell-Based Therapy.

In the past few years, intensive research has focused on corneal stem cells as an unlimited source for cell-based therapy in regenerative ophthalmology. Today, it is known that the cornea has at least two types of stem cells: limbal epithelial stem cells (LESCs) and corneal stromal stem cells (CSSCs). LESCs are used for regeneration of corneal surface, while CSSCs are used for regeneration of corneal stroma. Until now, various approaches and methods for isolation of LESCs and CSSCs and their successful transplantation have been described and tested in several preclinical studies and clinical trials. This review describes in detail phenotypic characteristics of LESCs and CSSCs and discusses their therapeutic potential in corneal regeneration. Since efficient and safe corneal stem cell-based therapy is still a challenging issue that requires continuous cooperation between researchers, clinicians, and patients, this review addresses the important limitations and suggests possible strategies for improvement of corneal stem cell-based therapy.

Measurement of Bone Mineral Density in Children with Cerebral Palsy from an Ethical Issue to a Diagnostic Necessity.

INTRODUCTION: Due to concerns about cumulative radiation exposure in the pediatric population, it is not standard practice to perform dual-energy X-ray absorptiometry (DXA) analysis in the diagnostic process of musculoskeletal disorders, such as cerebral palsy (CP). This study aimed to evaluate the bone mineral density (BMD) in children with CP and the ethical justification of applying DXA analysis in these children. Material and Methods. In this monocentric retrospective analysis, data were collected from children and adolescents with CP who were treated for a primary illness for three years. A clinical examination, which included a DXA analysis, recommended by the multidisciplinary team, was performed. After applying inclusion and exclusion criteria, 60 scans remained for statistical analysis. BMD and Z-scores for the lumbar spine (LS), and hip right and left femoral neck (RFN and LFN, respectively), and total hip (TH) were recorded. RESULTS: The average age of children with CP when DXA analysis was first performed was about 7 years. The BMD (mean ± SD) at LS (LS-BMD) of all patients was 0.612 ± 0.12, at RFN 0.555 ± 0.11, at LFN 0.572 ± 0.1, and at TH (TH-BMD) 0.581 ± 0.13. The values of the Z-score (mean ± SD) at LS of all patients were -2.5 ± 0.22, at RFN -2.2 ± 0.21, at LFN -2.25 (SD = 0.2), and at TH -2.3 (SD = 0.23). There was no statistical significance between age and gender; however, BMI, walking ability, fracture history, and pattern of CP had a significant impact on BMD and Z-score values of these children. CONCLUSION: The results of our study clearly indicate that children with CP have a higher risk of low BMD, osteoporosis, and bone fractures, which makes it ethically justifiable to perform the DXA analysis in these children.

Aging of Stem and Progenitor Cells: Mechanisms, Impact on Therapeutic Potential, and Rejuvenation.

It was once suggested that adult or tissue-specific stem cells may be immortal; however, several recently published data suggest that their efficacy is limited by natural aging in common with most other somatic cell types. Decreased activity of stem cells in old age raises questions as to whether the age of the donor should be considered during stem cell transplantation and at what age the donor stem cells should be harvested to ensure the largest possible number of viable, functional, and non-altered stem cells. Although stem cells remain active into old age, changes in stem cells and their microenvironments inhibit their regenerative potential. The impact of aging on stem cell populations differs between tissues and depends on a number intrinsic and extrinsic factors, including systemic changes associated with immune system alterations. In this review, we describe key mechanisms of stem and progenitor cell aging and techniques that are currently used to identify signs of stem cells aging. Furthermore, we focus on the impact of aging on the capacity for proliferation, differentiation, and clinical use of stem cells. Finally, we detail the aging of embryonic, mesenchymal, and induced pluripotent stem cells, with particular emphasis on aging mechanisms and rejuvenation.

Pharmacological Inhibition of Gal-3 in Mesenchymal Stem Cells Enhances Their Capacity to Promote Alternative Activation of Macrophages in Dextran Sulphate Sodium-Induced Colitis.

Transplantation of mesenchymal stem cells (MSCs) reduces the severity of dextran sulphate sodium- (DSS-) induced colitis. MSCs are able to secrete Galectin-3 (Gal-3), a protein known to affect proliferation, adhesion, and migration of immune cells. We investigate whether newly synthetized inhibitor of Gal-3 (Davanat) will affect production of Gal-3 in MSCs and enhance their potential to attenuate DSS-induced colitis. Pharmacological inhibition of Gal-3 in MSCs enhances their capacity to promote alternative activation of peritoneal macrophages in vitro and in vivo. Injection of MSCs cultured in the presence of Davanat increased concentration of IL-10 in sera of DSS-treated animals and markedly enhanced presence of alternatively activated and IL-10 producing macrophages in the colons of DSS-treated mice. Pharmacological inhibition of Gal-3 in MSCs significantly attenuates concentration of Gal-3 in sera of DSS-treated animals, indicating that MSCs produce Gal-3 in this disease. In conclusion, our findings indicate that Davanat could be used for improvement of MSC-mediated polarization towards immunosuppressive M2 phenotype of macrophages.

Stem cells as new agents for the treatment of infertility: current and future perspectives and challenges.

Stem cells are undifferentiated cells that are present in the embryonic, fetal, and adult stages of life and give rise to differentiated cells that make up the building blocks of tissue and organs. Due to their unlimited source and high differentiation potential, stem cells are considered as potentially new therapeutic agents for the treatment of infertility. Stem cells could be stimulated in vitro to develop various numbers of specialized cells including male and female gametes suggesting their potential use in reproductive medicine. During past few years a considerable progress in the derivation of male germ cells from pluripotent stem cells has been made. In addition, stem cell-based strategies for ovarian regeneration and oocyte production have been proposed as future clinical therapies for treating infertility in women. In this review, we summarized current knowledge and present future perspectives and challenges regarding the use of stem cells in reproductive medicine.