Roles of Vitamins D and K, Nutrition, and Lifestyle in Low-Energy Bone Fractures in Children and Young Adults.

The research on skeletal system health in children and young adults, while recognizing the important role of calcium and vitamin D, goes beyond these nutritional standards. This review focuses on the role of vitamin K in combination with vitamin D and other factors in bone health. The current understanding is that maintaining bone health and prevention of low-energy fractures in any pediatric population includes nutritional factors combined with an active lifestyle. Calcium, vitamin D, and vitamin K supplementation contribute independently and collectively to bone health. The beneficial role of vitamin K, particularly vitamin K2 as menaquinone-7 (MK-7), in bone and cardiovascular health is reasonably well supported scientifically, with several preclinical, epidemiological, and clinical studies published over the last decade. Osteocalcin and matrix-Gla (glutamate-containing) protein (MGP) exemplify vitamin K-dependent proteins involved in building bone matrix and keeping calcium from accumulating in the arterial walls, respectively. An important part of the mechanism of vitamin K involves carboxylation and posttranslational activation of the family of vitamin K-dependent proteins, which prevent expression of pro-inflammatory factors and support improvement in bone mineral concentration, bone mineral density, and the quality of bone matrix. Understanding the combined approach to a healthy skeletal system in children and young adults, including the roles of vitamins D and K, calcium, healthy diet, and exercise, is particularly important in view of reports of subclinical insufficiency of vitamins D and K in otherwise healthy pediatric populations with low-energy bone fractures.

Association between Vitamin D Receptor Polymorphism and Serum Vitamin D Levels in Children with Low-Energy Fractures.

OBJECTIVE: Fractures of bones, especially forearm fractures, are very common in children and their number is increasing. This study was designed to determine the impact of vitamin D serum levels and vitamin D receptor (VDR) polymorphisms on the occurrence of low-energy fractures in children. METHODS: The study group consisted of 100 children with clinically relevant bone fractures and a control group consisted of 127 children without fractures. Total vitamin D [25(OH)D3 plus 25(OH)D2] serum concentrations were evaluated in every patient. Genotypes for 4 restriction fragment length polymorphisms of the vitamin D receptor gene (FokI, ApaI, TaqI, and BsmI) were determined by standard polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) techniques. RESULTS: Differences in concentrations of vitamin D were observed between the group with bone fractures (median = 12 ng/ml) and the control group (median = 16 ng/ml; p = 0.000044). Higher levels of vitamin D reduced the risk of fracture by 1.06 times (p = 0.0005). No impact of particular VDR polymorphism on the occurrence of low-energy fractures in children was detected. However, there were significant differences in the prevalence of FokI polymorphism genotypes between the fracture and control groups (p = 0.05). Furthermore, the recessive "aa" genotype of ApaI polymorphism and the dominant "TT" genotype of TaqI polymorphism were associated with higher levels of vitamin D (p = 0.005 and p = 0.036, respectively). CONCLUSIONS: Vitamin D deficiency is an independent risk factor for fractures in children. ApaI polymorphism recessive "aa" and TaqI polymorphism dominant "TT" genotypes are associated with higher levels of vitamin D in serum.

Lyme disease with effusion either in hip or knee in children from Podlaskie region treated in clinic in 2004-2010.

OBJECTIVES: Lyme disease (LB) relatively commonly causes arthritis among patients, especially in LB endemic area. The aim of the study was to analyze the prevalence of LB in children with hip and knee effusion in the North Eastern region of Poland. Conclusions from our study should justify the need of taking into account LB in the diagnosis of hip or knee effusion in children. MATERIALS AND METHODS: The medical records of 321 children, aged 2-18 years, with synovitis of the hip or knee were reviewed. RESULTS: In 273 cases with hip effusion: 32 (11.72%) patients were diagnosed with LB, 233 (85.74%) with transient arthritis, 6 (2.19%) with purulent arthritis, and 2 (0.73%) with juvenile idiopathic arthritis. In 48 cases with knee effusion: 12 (25%) patients were diagnosed with Lyme arthritis, 24 (50%) with transient arthritis, 5 (10.42%) with reactive arthritis, 4 (8.33%) with juvenile idiopathic arthritis, and 3 (6.25%) with purulent arthritis. CONCLUSIONS: The high prevalence of LB in children with hip or knee effusion in endemic areas suggests the need of diagnostics also for LB in all patients presenting with acute monoarticular arthritis. Antibiotic treatment results in complete recovery.

[Congenital insensitivity to pain]. / Wrodzona niewrazliwosc na ból.

Congenital insensitivity to pain belongs to rare diseases called hereditary sensory neuropathy (HSN). The disturbance of sense and secondary harms are creating clinical picture. The aim of this report was to describe therapeutic problems with which we met with a three siblings with congenital insensitivity to pain. The authors have described three children with congenital insensitivity to pain. The disease was diagnosed at the age of 3-5. These children painlessly have broken their lower limbs. These fractures were late diagnosed what resulted in a badly healed deformation of legs. For this reason, the right knee of the oldest boy had to be stiffened. This boy had also late diagnosed the left hip luxation, and hematomas had arisen, which become filled with pus. The boy was in sepsis and a dramatic life-and-death struggle was performed. A purulent focuses were removed from abdomen and femoral head was also resected. The other two siblings had fractures and infections, but not such severe as the oldest boy. It is well known that a causal treatment of this disease in unknown. Patients must learn to avoid mechanical and thermal trauma. It is the only way to prevent complications of this disease.

Vitamin K Insufficiency in the Indian Population: Pilot Observational Epidemiology Study.

BACKGROUND: The fat-soluble K vitamins K1 and K2 play an essential role in the blood coagulation cascade and are made available predominantly through selective dietary intakes. They are less known for their nonessential roles in a family of vitamin K-dependent proteins that promote various functions of organs and systems in the body. A lack of vitamin K can characterize vitamin and nutritional element insufficiency, which is different from a clinically apparent vitamin deficiency. OBJECTIVE: This epidemiological study evaluated the nutritional status of vitamin K in a sample of the Indian population and vitamin K content in staple Indian foods. METHODS: Serum levels of vitamin K1 and vitamin K2 in the form of menaquinone-7 (MK-7) were assessed via high-performance liquid chromatography coupled with fluorescence detection in 209 patients with type 2 diabetes, 50 healthy volunteers, and common staple foods in India. RESULTS: After comparing populations with high and low serum vitamin K levels from various geographical regions, our results indicated that the sample of healthy Indian individuals and the sample of Indian patients with type 2 diabetes had low (insufficient) levels of vitamin K2 (MK-7; range 0.3-0.4 ng/mL). No significant differences existed in vitamin K1-related and MK-7-related values between healthy male and female subjects, between male and female subjects with diabetes, and between the healthy sample and the sample of patients with diabetes. The staple, commonly consumed Indian foods that were tested in this study had undetectable levels of vitamin K2, while levels of vitamin K1 varied widely (range 0-37 µg/100 g). CONCLUSIONS: Based on our sample's low serum levels of vitamin K2 (MK-7) as well as the low levels of vitamin K2 in their typical diet, we propose that the general Indian population could benefit from the consumption of vitamin K2 in the form of MK-7 supplements. TRIAL REGISTRATION: Clinical Trials Registry - India CTRI/2019/05/014246; http://ctri.nic.in/Clinicaltrials/showallp.php?mid1=21660&EncHid=&userName=014246; Clinical Trials Registry - India CTRI/2019/03/018278; http://ctri.nic.in/Clinicaltrials/showallp.php?mid1=32349&EncHid=&userName=018278.

Glycoconjugate markers of joint diseases.

A number of different types of glycoconjugate are found associated with joint tissue and fluids, comprising glycoproteins, glycolipids and glycosaminoglycans. Oligosaccharide chains of glycoconjugates are degraded by exoglycosidases, and the dominant exoglycosidase found in human blood, synovial fluid, the synovial membrane and chondrocytes of articular cartilage is HEX (N-acetyl-ß-hexosaminidase). HEX is localized mostly intracellularly in synovial cells. Serum activity of HEX may be used to monitor the course and efficiency of treatment of Lyme arthritis, and activity of HEX, above 10 µkat/kg of protein in the synovial fluid, suggests rheumatoid disease. There is a shortage of HEX inhibitors able to penetrate synoviocytes, so the development of drugs which inhibit synthesis and/or the activity of HEX will be a promising field for future investigations.

[The pirymethamine influence on hexosoaminidase gene expression in synovial cell culture--preliminary report]. / Wplyw pirymetaminy na ekspresje genów heksozoaminidazy w synowiocytach in vitro--doniesienie wstepne.

UNLABELLED: Inflammation process is leading to increasing of synovial fluid and value of its pressure. Moreover, the impairment of vascular flow within synovial membrane and increased permeability of blood vessels were described. The activity of lysosomal enzymes, such as N-acetyl-beta-glucosaminidase (HEX), was increased in patients with rheumatoid arthritis in comparison to health synovial fluid. It is supposed, that HEX takes part in joint destruction. The using of HEX inhibitors in synovial cell culture and evaluation of HEX mRNA expression before and after the adding of inhibitor may contribute in showing the new ways of understanding pathogenetic pathways of motion organ disorders. THE AIM of the study was to evaluate the expression of HEXA and HEXB genes in the synovial cell culture derived from human synovial inflammatory fluid obtained from patients suffered from rheumatoid arthritis. MATERIAL AND METHODS: The inflamed synovial fluid was taken from patients suffered from rheumatoid arthritis. The following solutions of potential inhibitor--pyrimethamine were used: 20 microg/ml, 10 microg/ml, 3 microg/ml and 1.5 microg/ml. Two separate control groups were established: control group 1 where only 0.6% of ethanol was added to the synovial cell culture; control group 2 where only 0.5% DMSO was added to the synovial cell culture. The relative quantitative real-time reverse transcriptase polymerase chain reaction (RT-PCR) was carried out. RESULTS. The difference in HEXA and HEXB expression was observed in synoviocytes obtained in synovial cell culture. Five time higher relative HEXA expression was determined after applying 3 microg/ml of pirymethamine compared with the control 1. The highest concentration of pirymethamine (10 and 20 microg/ml) caused the least elevation of HEXA expression. The slight decreased of HEXB expression was observed under the concentration of pirymethamine: 1.3 and 3 microg/ml. CONCLUSIONS. Pyrimethamine contributes to regulating the HEX gene expression from synovial cells. The change in gene expression level is dependent on the concentration of the pirymethamine. Our preliminary data don't let us establish the concentration of pyrimethamine that may significantly inhibit HEXA and HEXB expression. Further study may be conducted to put new insight into the pathogenesis of joint destruction in the course of rheumatoid arthritis.

IGF-I and IGF-binding proteins in articular exudates of children with post-traumatic knee damage and juvenile idiopathic arthritis.

OBJECTIVE: IGF-I stimulates multiple functions of connective tissue cells and its activity is modulated by IGF-binding proteins (BPs). Some metalloproteinases are expected to modify IGF-I activity by digestion of IGF-BPs. It was decided to evaluate the concentration of IGF-I, IGF-BPs and the activity of gelatinases A and B in knee exudates of children with post-traumatic damage (PTD) and children with juvenile idiopathic arthritis (JIA) in comparison with those in the sera of the same patients. METHODS: ELISA (for IGF-I assay), polyacrylamine gel electrophoresis following Western immunoblotting (for IGF-I and IGF-BPs expression), and zymography (for gelatinase detection) were used. RESULTS: The knee exudates, especially those taken from patients with JIA, contained large amounts of IGF-I. The exudates of PTD and JIA patients contained some forms of IGF-BP-1 of molecular weight lower than those occurring in serum. Low expression BP-3 and high activity of gelatinase B were detected in the JIA exudates. CONCLUSIONS: The high gelatinase activities in exudates imply joint tissue damage. The cellular response to damage of this kind is an increase in IGF-I production, which stimulates repair processes. High proteolytic activities of gelatinase B in JIA patients may lower the amount of BP-3, possibly causing a relative decrease of IGF-I concentration and impairing the reparation processes stimulated by IGF-I.

Activity of lysosomal exoglycosidases in serum and synovial fluid in patients with chronic Lyme and rheumatoid arthritis.

Lysosomal exoglycosidases participate in the destruction of the articular cartilage by cleaving glycoside bonds in glycoproteins and proteoglycans. The aim of the study was to determine the activity of exoglycosidases: hexosaminidase, beta-glucuronidase, beta-galactosidase, alpha-mannosidase and alpha-fucosidase in serum and synovial fluid of patients with Lyme and rheumatoid arthritis. The study group consisted of 10 patients with chronic Lyme arthritis (age 18 - 74 y), 13 with rheumatoid arthritis (age 32 - 70 y) and 10 with juvenile idiopathic arthritis (age 8 - 17 y). The control group consisted of 9 healthy volunteers (age 24 - 62 y). The activity of the exoglycosidases was determined with the p-nitrophenyl derivatives of sugars as substrates. A significant increase of the activity of all the exoglycosidases in serum and in synovial fluid of the patients with different forms of arthritis was found. The ratio of synovial fluid/serum activity of exoglycosidases was above 2.0 in LA but not in JIA and RA patients. As the main source of exoglycosidases in the joint is the synovial membrane, this result supports the appropriateness of therapeutic synovectomy in chronic Lyme arthritis with knee effusion. The serum activity of hexosaminidase may be used in monitoring the course of Lyme arthritis and the efficiency of treatment.

Profile of exoglycosidases in synovial cell cultures derived from human synovial membrane.

OBJECTIVE: Determining the activity of lysosomal exoglycosidases in tissue cultures of synoviocytes derived from the knee joints of patients with injured anterior cruciate ligaments (ACL), juvenile idiopathic arthritis (JIA), and rheumatoid arthritis (RA). METHODS: The following exoglycosidases in cultured synoviocytes were analyzed with p-nitrophenyl derivatives of appropriate sugars as substrates: hexosaminidase (HEX) and its isoenzyme A (HEX-A), beta-glucuronidase (GluA), beta-galactosidase (GAL), alpha-mannosidase (MAN), and alpha-fucosidase (FUC). RESULTS: In our cell cultures, fibroblast-like synovial cells (FLS) dominated. In the group of patients with ACL-injuries, and in the groups of patients with JIA and RA, the activity of the investigated exoglycosidases was significantly higher in the intra- rather than in the extracellular compartment. Hexosaminidase was the predominant exoglycosidase. Stimulation of synoviocytes by IL-1beta in cell cultures significantly increased the activity of HEX, HEX-A, and GluA in both compartments, as well as of GAL, MAN, and FUC in the intracellular compartment. Stimulation by IL-1beta rheumatoidal synoviocytes increased by 128-201% the activity of HEX and HEX A in intracellular compartments and 33-72% in extracellular compartment. CONCLUSIONS: The profile of lysosomal exoglycosidases in a cell culture of human synoviocytes is similar, but not identical, to those in the knee joint. Hexosaminidase is the dominant glycosidase in cultured unstimulated and IL-1beta-stimulated human synoviocytes. The HEX inhibitors may be new drugs for the treatment of inflamed knee joints.

Decreased Levels of Circulating Carboxylated Osteocalcin in Children with Low Energy Fractures: A Pilot Study.

OBJECTIVE: In the past decades, an increased interest in the roles of vitamin D and K has become evident, in particular in relation to bone health and prevention of bone fractures. The aim of the current study was to evaluate vitamin D and K status in children with low-energy fractures and in children without fractures. METHODS: The study group of 20 children (14 boys, 6 girls) aged 5 to 15 years old, with radiologically confirmed low-energy fractures was compared with the control group of 19 healthy children (9 boys, 10 girls), aged 7 to 17 years old, without fractures. Total vitamin D (25(OH)D3 plus 25(OH)D2), calcium, BALP (bone alkaline phosphatase), NTx (N-terminal telopeptide), and uncarboxylated (ucOC) and carboxylated osteocalcin (cOC) serum concentrations were evaluated. Ratio of serum uncarboxylated osteocalcin to serum carboxylated osteocalcin ucOC:cOC (UCR) was used as an indicator of bone vitamin K status. Logistic regression models were created to establish UCR influence for odds ratio of low-energy fractures in both groups. RESULTS: There were no statistically significant differences in the serum calcium, NTx, BALP, or total vitamin D levels between the two groups. There was, however, a statistically significant difference in the UCR ratio. The median UCR in the fracture group was 0.471 compared with the control group value of 0.245 (p < 0.0001). In the logistic regression analysis, odds ratio of low-energy fractures for UCR was calculated, with an increased risk of fractures by some 78.3 times. CONCLUSIONS: In this pilot study, better vitamin K status expressed as the ratio of ucOC:cOC-UCR—is positively and statistically significantly correlated with lower rate of low-energy fracture incidence.

Evaluation of Treatment of Low-energy Distal Radial Fractures in Postmenopausal Women.

BACKGROUND: Distal radial fractures are one of the most common injuries seen in traumatology. Most are treated conservatively with closed reduction and immobilisation in a plaster cast. However, this method does not always allow for achieving and maintaining normal fracture reduction in unstable fractures. The aim of this study was assess clinical and radiographic outcomes of treatment of distal radial fractures depending on the method used. MATERIAL AND METHODS: A total of 77 postmenopausal female subjects were divided into three subgroups, depending on the treatment methods: 1. closed reduction and immobilisation in a plaster cast; 2. closed reduction and percutaneous fixation with K wires; 3. open reduction and fixation with a locking plate. Follow-up examinations took place at 4 and 12 months post injury and involved measurements of the range of motion in the radiocarpal joint and hand grip strength. The results were classified according to the Mayo Wrist Score. X-ray images were used to mark parameters of radiographic assessment of the distal radius and the results were classified according to the radiographic Lidstrom score. RESULTS: The percentage of excellent and good results was significantly higher in both surgically treated groups (plate: 92.6%, K wires: 88.0%) than in the group treated conservatively (48%). CONCLUSION: 1.The percentage of excellent and good results from both surgically treated groups (plate: 92.6%, K wires: 88.0%) was significantly higher than in the group treated conservatively (48%). 2. Open reduction with locking plate fixation of distal radial fractures produces better functional outcomes in the early postoperative period and reduces the risk of development of complex regional pain syndrome.

Differential effect of platelet-rich plasma fractions on ß1-integrin signaling, collagen biosynthesis, and prolidase activity in human skin fibroblasts.

The study was conducted to evaluate the effects of platelet-rich plasma (PRP), supernatant of PRP (SPRP) obtained by centrifugation, and supernatant of activated PRP (SActi-PRP) obtained by Ca2+ solution-treated PRP on collagen biosynthesis, prolidase activity, and ß1-integrin signaling in cultured human skin fibroblasts. Incubation of fibroblasts with 5% PRP for 24 h contributed to ~5-fold increase in collagen biosynthesis compared to the control. In the cells treated with 5% of SPRP or SActi-PRP, collagen biosynthesis showed a 3-fold increase of the control. PRP, SPRP, and SActi-PRP stimulated prolidase activity similar to collagen biosynthesis. Collagen biosynthesis and prolidase activity are regulated by ß1-integrin receptor signaling. Incubation of fibroblasts with PRP for 24 h contributed to a dose-dependent increase in the expression of ß1-integrin receptor, while SActi-PRP increased the process to a much lower extent. SPRP had no effect on the ß1-integrin receptor expression. All the studied fractions of blood increased the expression of FAK as well as the expression of phosphorylated MAP-kinases. However, PRP was found to be the most effective stimulator of expression of these particular kinases. These studies suggest that a complex of factors, including growth factors, adhesion molecules, and prolidase contained in PRP, all evoke growth and collagen-promoting activities in human dermal fibroblasts.

Is the repair of articular cartilage lesion by costal chondrocyte transplantation donor age-dependent? An experimental study in rabbits.

The repair of chondral injuries is a very important problem and a subject of many experimental and clinical studies. Different techniques to induce articular cartilage repair are under investigation. In the present study, we have investigated whether the repair of articular cartilage folowing costal chondrocyte transplantation is donor age-dependent. Transplantation of costal chondrocytes from 4- and 24-week old donors, with artificially induced femoral cartilage lesion, was performed on fourteen 20-week-old New Zealand White male rabbits. In the control group, the lesion was left without chondrocyte transplantation. The evaluation of the cartilage repair was performed after 12 weeks of transplantation. We analyzed the macroscopic and histological appearance of the newly formed tissue. Immunohistochemistry was also performed using monoclonal antibodies against rabbit collagen type II. The newly formed tissue had a hyaline-like appearance in most of the lesions after chondrocyte transplantation. Positive immunohistochemical reaction for collagen II was also observed in both groups with transplanted chondrocytes. Cartilage from adult donors required longer isolation time and induced slightly poorer repair. However, hyaline-like cartilage was observed in most specimens from this group, in contrast to the control group, where fibrous connective tissue filled the lesions. Rabbit costal chondrocytes seem to be a potentially useful material for inducing articular cartilage repair and, even more important, they can also be derived from adult, sexually mature animals.

Long-term outcome of early treatment of developmental hip dysplasia using an abduction splint.

Background. Treatment of congenital hip dysplasia, when implemented in the first weeks of life, gives a good outcome. Very few publications, however, have addressed the anatomical remodeling of the affected hip. In this study, we evaluate the anatomical outcome of the treatment applied. Material and methods. We examined 89 children diagnosed with congenital hip dysplasia in the first three months of life and then treated with an abduction device, for a total of 148 hips. The time of follow-up varied from 8 to 13 years. All these children were given a clinical examination according to McKay, along with Severin X-ray classification. Results. Before treatment was implemented, the patients had been diagnosed as types IIc (56 hips, 37.8%), IId (34 hips, 22.9%), III (40 hips, 27.1%), and IV (18 hips, 12.2%). In one hip final assessment showed signs of aseptic necrosis of the proximal femur. 147 hips showed total remodeling, and in the Severin X-ray classification scheme were evaluated as type I. Conclusions. Severin X-ray clasification is easy to implement and in our material corresponds with the clinical evaluation according to McKay. Early implementation of treatment with an abduction device is worthwhile and gives a satisfactory outcome.

Inhibition of TNF-α, IL-1α, and IL-1ß by Pretreatment of Human Monocyte-Derived Macrophages with Menaquinone-7 and Cell Activation with TLR Agonists In Vitro.

Circulatory markers of low-grade inflammation such as tumor necrosis factor-alpha (TNF-α), interleukin-1 alpha (IL-1α), and interleukin-1 beta (IL-1ß) positively correlate with endothelial damage, atheroma formation, cardiovascular disease, and aging. The natural vitamin K2-menaquinone-7 (MK-7) added to the cell culture of human monocyte-derived macrophages (hMDMs) at the same time as toll-like receptor (TLR) agonists did not influence the production of TNF-α. When the cells were pretreated up to 6 h with MK-7 before treatment with TLR agonists, MK-7 did not inhibit significantly the production of TNF-α after the TLR activation. However, 30 h pretreatment of hMDMs with at least 10 µM of MK-7 effectively and dose dependently inhibited the proinflammatory function of hMDMs. Pretreatment of hMDMs with 10 µM of MK-7 for 30 h resulted in 20% inhibition of TNF-α production after lipopolysaccharide (LPS) activation (P < .05) and 43% inhibition after macrophage-activating lipopeptide (MALP) activation (P < .001). Pathogen-associated molecular pattern (PMPP) activation was inhibited by 20% with MK-7 pretreatment; however, this inhibition was not statistically significant. The 30 h pretreatment of a THP-1-differentiated monocyte cell line with MK-7 resulted in a dose-dependent downregulation of TNFα, IL-1α, and IL-1ß gene expression as evaluated by RNA semiquantitative reverse transcription polymerase chain reaction (RT-PCR). MK-7 is able to modulate immune and inflammatory reactions in the dose-response inhibition of TNF-α, IL-1α, and IL-1ß gene expression and protein production by the healthy hMDMs in vitro.

Phenotype variability in a daughter and father with mild osteogenesis imperfecta correlated with collagen and prolidase levels in cultured skin fibroblasts.

Studies of collagen biosynthesis and prolidase activity were performed on cultured skin fibroblasts obtained from a female patient and her father, who displayed variable phenotypes of mild osteogenesis imperfecta (OI). For comparison, the same studies were also performed on age-matched controls. Biosynthesis of collagen in fibroblasts of the less affected father was reduced to approximately 50% of control levels, whereas in cells of the more severely affected daughter, it was decreased to about 20% of control levels. Furthermore, the decrease in collagen synthesis in OI fibroblasts was accompanied by a parallel decrease in prolidase activity and expression of beta1 integrin and insulin-like growth factor-I (IGF-I) receptors recovered from the cells. Therefore, prolidase, as well as IGF-I and beta1 integrin receptors involved in collagen metabolism regulation, may represent important factors influencing OI phenotype.

[Activity of N-acetylo-beta-hexosamninidase in joint fluid from knee and serum of patients with rheumatoid arthritis and osteoarthritis]. / Aktywnosc N-acetylo-beta-heksozoaminidazy w plynie stawowym i surowicy krwi chorych z reumatoidalnym zapaleniem stawów i artroza.

N-acetyl-beta-hexosoaminidase (Hex) is a lysosomal enzyme which releases N-acetylaminohexose from non reducing end of glycosaminoglycans, glycoproteins and glycolipids, taking part in degradation of these substances. It is not known what role Hex plays in the degradation of joints in rheumatoid arthritis and osteoarthritis. The aim of our work was evaluation of Hex activity in synovial fluid and serum of patients with rheumatoid arthritis and osteoarthritis. The investigation was performed on material taken from 28 patients with rheumatoid arthritis aged 22-74 years with III or IV stage of disease and 26 patients with osteo-arthritis aged 41-75 years. The synovial fluid was collected from the knee joint during puncture. Hex activity was also determined in serum of healthy people at the age 25-40 years which constitute a control group. Hex activity was determined by the method of Chatterjee et al. modified by Zwierz et al. The concentration of Hex activity in synovial fluid of patients with rheumatoid arthritis was 15.2 nmol/ml/min and 3-4 times excedeed the serum value in these patients. In osteoarthrosis patients Hex concentration in synovial fluid was 6.15 nmol/ml/min. In serum of all investigated groups, concentration of Hex activity was 4.0-4.7 nml/ml/min. The specific activity of Hex (calculated as a constant amount of protein) in synovial fluid of patients with rheumatoid arthritis was significantly higher than in serum of these persons (p<0.017 and 0.014 respectively).

Study of the protective effects of nootropic agents against neuronal damage induced by amyloid-beta (fragment 25-35) in cultured hippocampal neurons.

BACKGROUND: Alzheimer's disease (AD) is a common neurodegenerative disorder, in which progressive neuron loss, mainly in the hippocampus, is observed. The critical events in the pathogenesis of AD are associated with accumulation of ß-amyloid (Aß) peptides in the brain. Deposits of Aß initiate a neurotoxic "cascade" leading to apoptotic death of neurons. Aim of this study was to assess a putative neuroprotective effects of two nootropic drugs: piracetam (PIR) and levetiracetam (LEV) on Aß-injured hippocampal neurons in culture. METHODS: Primary cultures of rat's hippocampal neurons at 7 day in vitro were exposed to Aß(25-35) in the presence or absence of nootropics in varied concentrations. Flow cytometry with Annexin V/PI staining was used for counting and establishing neurons as viable, necrotic or apoptotic. Additionally, release of lactate dehydrogenase (LDH) to the culture medium, as a marker of cell death, was evaluated. RESULTS: Aß(25-35) caused concentration-dependent death of about one third number of hippocampal neurons, mainly through an apoptotic pathway. In drugs-containing cultures, number of neurons injured with 20 µM Aß(25-35) was about one-third lesser for PIR and almost two-fold lesser for LEV. When 40 µM Aß(25-35) was used, only LEV exerted beneficial neuroprotective action, while PIR was ineffective. CONCLUSIONS: Our results suggest the protective potential of both studied nootropics against Aß-induced death of cultured hippocampal neurons with more powerful neuroprotective effects of LEV.

Fibroblast-Like Synovial Cells in Rheumatoid Arthritis--the Impact of Infliximab on Hexosaminidase Activity.

BACKGROUND: The effect of multiple infusions of infliximab (INF), a chimeric anti-tumor necrosis factor alpha antibody, on the concentration of hexosaminidase (HEX) activity in a synovial cell culture derived from human synovial inflamed fluid obtained from patients suffering from rheumatoid arthritis (RA) has been evaluated. OBJECTIVES: The aim of this study was to prove INF efficacy in RA. MATERIAL AND METHODS: Inflamed synovial fluid was taken from RA patients (a study group) and patients who had undergone knee trauma within 7 days (a control group). The following solutions of infliximab were used: 40, 60 and 140 µg/mL. Determination of the concentration of HEX activity in cell cultures was performed after 24, 48, 72 and 96 h of infliximab administration. To identify synoviocytes in cell culture immunohistochemical staining with vimentin and pancytokeratin was performed. RESULTS: A predominance of fibroblast-like synovial cells has been observed in the study group. In the control group the concentration of HEX activity without adding infliximab to the cell culture was 283.00 nkat/mL. After 96 h of incubation with infliximab, the concentrations of HEX activity in cultured synoviocytes according to infliximab doses of 40, 60 and 140 µg/mL were respectively: 280.00, 271.50 and 293.50 nkat/mL. In the study group, the concentration of HEX activity without adding infliximab to the cell culture was 542.27 nkat/mL. The final concentrations of HEX activity of cultured fibroblast-like synovial cells measured after 96 h of incubation with infliximab were: 471.72, 498.27 and 556.72 nkat/mL, according to infliximab doses of 40, 60 and 140 µg/mL. In all groups (besides the infliximab concentration of 140 µg/mL after 96 h of incubation), the level of concentration of HEX activity was significantly higher in the study group compared to the control group, irrespective of infliximab concentration and time of infliximab incubation. CONCLUSIONS: Infliximab changes the concentration of HEX activity depending on the drug dose and time of administration.