N-acetyl-b-glucosaminidase Research Articles

Microplastics derived from polymer-coated fertilizer altered soil properties and bacterial community in a Cd-contaminated soil

With the extensive use of polymer-coated fertilizer, microplastics (MPs) pollution in agricultural soil raises worldwide concerns. While very few studies focalized the effects of polymer-coated fertilizer MPs exposure to acid-contaminated soil. Changes in soil properties, enzymatic activity, and microbial community structure were investigated via the addition of 0.1 % and 1 % (w/w) of polyethylene (PE) and polyurethane (PU) in acid soil. The results showed that two types of MPs addition decreased soil pH and MBC contents, stimulated DTPA (cadmium extracted by diethylenetriamine-pentaacetic acid)-Cd (extracted cadmium) contents, β-glucosidase (BG) and N-acetyl-b-glucosaminidase (NAG) activities significantly. The diversity and richness of fungi was dropped sharply after the addition of 0.1 % PE and PU MPs, but there was the opposite result in fungi. The relative abundance of phylum Mortierellomycota increased significantly in 1 % PE and PU treatments, inferring that the fungus associated with the degradation of recalcitrant carbon source in soil enhanced by the input of MPs. Overall, our research demonstrated that there is still a risk of increased metal bioavailability with the addition of polymer-coated fertilizer MPs, but the fluctuation of soil enzymatic activities and microbial community structure were much more pronounced affected by soil properties via the addition of PE and PU in soil.

Urinary and Serum N-acetyl B-Glucosaminidase as Biomarkers of Albuminuria in Patients with Type 2 Diabetes

Objectives: Osteoarthritis is a widespread degenerative defect of the articular cartilage connected withhypertrophic bone changes. Worldwide, obesity is one of the most common risk factor for such disorder.Current study was designed to investigate effect of this factor in Iraqi OA patients. Subjects and method:Total of 75 volunteers were enrolled in this study (50 patients and 25 subjects as controls). BMI and lipidprofile were measured for each subject.Results: Our study showed significant elevations (p value< 0.05) in each of cholesterol, TG, LDL, andVLDL as well as in BMI while showed nonsignificant difference in HDL in OA patients compared to healthyindividuals.Conclusion: Obesity and disturbance of lipid profile may play substantial roll in development of OA in Iraqipatients.

Intravitreal thalidomide ameliorates inflammation in a model of experimental uveitis induced by BCG

Uveitis encompasses a heterogeneous and complex group of conditions characterized by intraocular inflammation, frequently affecting young individuals and representing an important cause of irreversible blindness worldwide. Animal models have been critical to understand etiology and pathogenesis of uveitis, being also employed to assess new therapeutic strategies, preceding human studies. However, there is still a need of developing and studying different models, due to the difficulties in recapitulating all forms of human uveitis effectively. Although corticosteroids are usually the first-line therapy for non-infectious uveitis, their long-term use is limited by potentially serious side effects in all possible delivery routes. Thus, thalidomide, a drug with anti-inflammatory and antiangiogenic properties, was investigated in a novel experimental model of uveitis, induced by Mycobacterium bovis Calmette-Guérin Bacillus (BCG), in rabbits. The experimental protocol consisted of two subcutaneous injections of BCG, followed by two intravitreal injections of the same antigen, inducing panuveitis. Animals were treated with a single intravitreal injection of thalidomide suspension or PBS. Clinical manifestations of uveitis improved after intravitreal thalidomide, involving both anterior and posterior segments. Protein content, N-acetyl-b-glucosaminidase (NAG) and myeloperoxidase (MPO) activities were elevated in ocular tissues after disease induction, further decreasing post-treatment with intravitreal thalidomide. This therapeutic response was also confirmed on ocular electrophysiology, as well as histopathology. This experimental model induced panuveitis in rabbits using a low-cost mycobacterial antigen, with intraocular inflammation subsequently improving after treatment. Intravitreal thalidomide may be a potential alternative to treat intraocular inflammation in corticosteroid-sparing therapies.

Urinary and Serum N-acetyl B-Glucosaminidase as Biomarkers of Albuminuria in Patients with Type 2 Diabetes

Background: Diabetic nephropathy is a serious kidney-related complication of type 1 diabetes and type 2 diabetes. It is also called diabetic kidney disease. About 25% of people with diabetes eventually develop kidney disease. The enzyme N-Acetyl-?-glucosaminidase (NAG) (EC: 3.2.1.30) is one of lysosomal acid hydrolases enzyme present in many body tissues with a high molecular weight (~ 140 kDa). It breaks chemical bonds of glycoside and amino sugars which form structural components in many tissues. Different pieces of cells need to be degraded and disposed of, including the cell membrane. Method: By using ELISA kit, we measured urine and serum level of N-acetyl B-Glucosaminidase in 30 patients diabetes with Microalbuminuria: ACR: 30 mg/g with 30 healthy volunteers enlisted as normal controls. Result: Urine concentration of NAG in macro and micro- groups was comparable (13.23±1.04 ng/mL and 13.1±1.46 ng/mL, respectively) with no significant difference, while both groups showed highly significant difference compared with normo- group (5.15±2.11 ng/mL) On the other hand, serum concentration of NAG in normo- micro- and macroabluminuria was 1.2±0.3 ng/mL, 2.5±0.58 ng/mL and 3.2±0.77 ng/mL, respectively, with highly significant differences between the three groups. Conclusion: N-Acetyl-?-Glucosaminidase: the present study, diabetic nephropathy was associated with elevated urinary and serum NAG values compared to a control group. This increase in NAG was parallel to the severity of renal involvement with a characteristic increasing trend was observed among the study groups regarding albuminuria

The role of nitric oxide signaling in renoprotective effects of hydrogen sulfide against chronic kidney disease in rats: Involvement of oxidative stress, autophagy and apoptosis.

The interplay between H2 S and nitric oxide (NO) is thought to contribute to renal functions. The current study was designed to assess the role of NO in mediating the renoprotective effects of hydrogen sulfide in the 5/6 nephrectomy (5/6 Nx) animal model. Forty rats were randomly assigned to 5 experimental groups: (a) Sham; (b) 5/6 Nx; (c) 5/6Nx+sodium hydrosulfide-a donor of H 2 S, (5/6Nx+sodium hydrosulfide [NaHS]); (d) 5/6Nx+NaHS+ L-NAME (a nonspecific nitric oxide synthase [NOS] inhibitor); (e) 5/6Nx+NaHS+aminoguanidine (a selective inhibitor of inducible NOS [iNOS]). Twelve weeks after 5/6 Nx, we assessed the expressions of iNOS and endothelial NOS (eNOS), oxidative/antioxidant status, renal fibrosis, urine N-acetyl-b-glucosaminidase (NAG) activity as the markers of kidney injury and various markers of apoptosis, inflammation, remodeling, and autophagy. NaHS treatment protected the animals against chronic kidney injury as depicted by improved oxidative/antioxidant status, reduced apoptosis, and autophagy and attenuated messenger RNA (mRNA) expression of genes associated with inflammation, remodeling, and NAG activity. Eight weeks Nω-nitro-l-arginine methyl ester ( L-NAME) administration reduced the protective effects of hydrogen sulfide. In contrast, aminoguanidine augmented the beneficial effects of hydrogen sulfide. Our finding revealed some fascinating interactions between NO and H 2 S in the kidney. Moreover, the study suggests that NO, in an isoform-dependent manner, can exert renoprotective effects in 5/6 Nx model of CKD.

Application of the Benchmark Dose (BMD) Method to Identify Thresholds of Cadmium-Induced Renal Effects in Non-Polluted Areas in China.

The benchmark dose (BMD) method has been increasingly used to assess the health risks of cadmium (Cd) in epidemiological studies. The aim of our study was to estimate the threshold levels of urinary Cd (UCd) using the BMD method in a general population of Jiangshan City, Zhejiang Province of China. In our study, a total of 934 people (469 men, 465 women) were recruited and morning urine samples were collected from all the participants. Levels of Cd, creatinine, and renal dysfunction indicators such as retinol binding protein (RBP), β2-microglobulin (β2-MG), and N-acetyl-b-glucosaminidase (NAG) in urine were detected for analysis of BMD and BMD low (BMDL) of UCd. RBP, β2-MG, and NAG in urine all correlated significantly (P < 0.001) with UCd except of age (P = 0.767). When the benchmark response (BMR) was 5%, the BMD/BMDL of UCd for RBP, β2-MG, and NAG was 1.69/ 0.89, 1.24/0.62, 0.85/0.49 μg/g Cr in men and 1.70/0.76, 1.35/0.64, 1.36/0.65 μg/g Cr in women, respectively. If the BMR was set at 10%, the BMD/BMDL of UCd for RBP, β2-MG, and NAG was 2.44/1.59, 2.09/1.30, 1.80/1.04 μg/g Cr in men and 2.43/1.53, 2.10/1.34, 2.31/1.37 μg/g Cr in women, respectively. Our results provided evidence for Cd-induced tubular effects in cadmium non-polluted areas in China. Both β2-MG and NAG were more sensitive than RBP in response to Cd exposure. But β2-MG was the most sensitive indicator in women, and NAG was the most sensitive one in men.

Development of thalidomide-loaded biodegradable devices and evaluation of the effect on inhibition of inflammation and angiogenesis after subcutaneous application

PurposeTo develop thalidomide-loaded poly-lactide-co-glycolide implants and evaluate its in vivo release and biological activity against inflammation and angiogenesis after subcutaneous administration. MethodsImplants were prepared by the hot molding technique and characterized using stereomicroscopy, thermal analysis and X-ray diffraction. Swiss mice, divided in groups 1–3, received a subcutaneous implant containing 25% (w/w), 50% (w/w) or 75% (w/w) of thalidomide, respectively (n=6). The drug levels were determined during a 28-day study period. The toxicity associated with the implants was evaluated by light microscopy. The potential of the developed implant in the inhibition of inflammation and angiogenesis was evaluated in vivo using the sponge model. ResultsThalidomide implant was developed and its characterization proved the stability of the drug and the polymer during preparation. Release profiles in vivo demonstrated an extended release of thalidomide from the implants during the 28 days. Histological evaluation did not show any sign of intense local inflammatory response to the presence of the implants in the subcutaneous pouch. The thalidomide implant reduced the number of vessels and N-acetyl-b-glucosaminidase (NAG) in vivo. ConclusionThe biodegradable implants delivered safe doses of thalidomide that were also effective to induce angiogenesis and inflammation regression.

Lymphocytic enzymes and lipid peroxidation in patients with metabolic syndrome

Metabolic syndrome (MetS) is considered a state of chronic inflammation. This study aimed to ascertain selected parameters of purinergic and cholinergic systems related to glucose metabolism and inflammation, as well as (γ)-glutamyltransferase (GGT) and N-acetyl-b-glucosaminidase (NAG) activities and lipoperoxidation in lymphocytes of patients with MetS. The adenosine deaminase (ADA), dipeptidyl peptidase IV (DPP-IV), acetylcholinesterase (AChE), GGT and NAG activities, as well as thiobarbituric acid reactive substances (TBARS) levels were investigated in lymphocytes of patients with MetS (n=38) and healthy volunteers (n=41). We also evaluated the insulin levels, anthropometric measurements and routine biochemical analyses. ADA (p<0.05), DPP-IV and AChE (p<0.0001) activities were higher in patients with MetS when compared to the control group. Furthermore, we observed correlations between ADA and DPP-IV activities (p=0.0002; r=0.5945), TBARS levels and ADA (p=0.0021; r=0.5172) and DPP-IV activities (p=0.0022; r=0.5010). Our findings showed that MetS might cause tissue distress that disturbed lymphocytic ADA, DPP-IV and AChE activities in response to inflammatory stimuli. These alterations evidence clinical abnormalities, since these enzymatic systems are able to regulate several aspects of adipose tissue function and inflammatory state of MetS and could be used successfully both for preventing and for halting the progression of MetS.

640 Urinary Markers for Acute Tubular Injury Following Paediatric Cardiopulmonary Bypass

Background and aims: Cardiopulmonary bypass (CPB) has proved to alter organs functions. The aim of this study was to evaluate the reliability of urinary biomarkers when diagnosing acute kidney injury (AKI) after CBP. Methods: Prospective, observational study. Paediatric patients who underwent CPB were included during a 4 month period. Surgical aggression was related to aortic cross-clamp (ACC), circulatory arrest, severe hypothermia and CPB duration. Postoperative AKI was based on serum creatinine (Cr) elevation by 50% from baseline or need of dialysis. Cystatin C (CyC), N-acetylb- glucosaminidase (NAG) and a1-microglobulin (a1mg) urinary values and plasmatic CyC were analysed using fractional excretion of CyC (FEcc), NAG/Cr ratio (normal 15 U/g Cr) and a1mg/Cr ratio (normal 0.1 - 14 mg/g Cr). Data presented as median (P25-P75). Results: 31 patients were included. Median age was 10 months (4-78 months). 11 children presented postoperative AKI. 29 patients showed increased excretion of NAG, median 51.0 (23.8- 73.8 UI/g Cr). a1mg/cr values were elevated in all children, median 172.9 (70.6-392.9 mg/g Cr). a1mg and FEcc values were higher amongst children presenting AKI (0.14%, 330 mg/g Cr vs 0.06%, 96 mg/g Cr, P< 0.02). In this group CPB duration and ACC time were also higher (215, 108 vs 156, 77 minutes, P< 0.03). Correlation between FEcc and a1mg/cr as well as between both FEcc and a1mg/ cr and ACC time was found. Conclusions: Tubular injury is frequent amongst children undergoing CBP. Magnitude of surgical aggressions might influence postoperative AKI. FEcc and a1mg/cr could be of use when analysing AKI after CBP.

Evaluation of a synchronous twin‐pulse technique for shock wave lithotripsy: a prospective randomized study of effectiveness and safety in comparison to standard single‐pulse technique

To asses the efficacy and safety of bidirectional synchronous twin-pulse extracorporeal shock wave lithotripsy (ESWL) compared with standard ESWL. Between March 2003 and December 2006, 240 patients with a radio-opaque single renal stone of <or=25 mm were randomized to treatment either by the Twinheads (TH) lithotripter (FMD, Lorton, Virginia, USA) or the Dornier Lithotripter S (DLS, Dornier MedTech Europe GmbH, Germering, Germany). Before and after ESWL, urinary N-acetyl-B-glucosaminidase (NAG) levels were assessed and patients were evaluated with dynamic MRI. The efficacy and complications were compared, with success defined as no residual fragments. For stones of >10 mm the rate for the failure of disintegration was 13.3% for the DLS vs 1.4% for the TH (P = 0.009). For stones of <or=10 mm the stone-free rate was 74.4% for the TH vs 67.7% for the DLS (P = 0.6), while for stones of >10 mm it was 78.1% and 66.7%, respectively (P = 0.14). The median (range) number of sessions in both groups was 2 (1-5). After ESWL urinary NAG levels were increased significantly in both groups; in the TH group it declined below the level before ESWL after 2 days, while in the DLS group it remained high after 7 days. In the DLS group four patients developed subcapsular or parenchymal haematoma after ESWL, vs none in the TH group. There was loss of corticomedullary differentiation after ESWL in three patients in the DLS group and only one in the TH group. In the DLS group there was a statistically significantly decrease in bilateral renal perfusion after ESWL, but no changes in the TH group. Synchronous twin-pulse ESWL has clinical advantages over standard ESWL in terms of safety and efficacy.

Urinary N-Acetyl B Glucosaminidase as an Earlier Marker of Diabetic Nephropathy and Influence of Low-Dose Perindopril/Indapamide Combination

Introduction. Tubulointerstitial injury is both a key feature of diabetic nephropathy and an important predictor of renal dysfunction. N-Acetyl B glucosaminidase (NAG) is derived from proximal tubular cells and is widely used to evaluate tubular renal function. Objective. The objective of this study is whether NAG can be used as an early marker of diabetic nephropathy by comparing the urinary NAG levels between healthy controls and diabetic patients and determining changes in urinary NAG excretion after treatment with low-dose combination perindopril (2 mg)/indapamide (0.625 mg)/o.d. Materials and Methods. A total of 50 patients (29 female) with type II diabetes mellitus applying to our diabetes outpatient clinics for the first time were included in our study (Group 1). Diabetic patients were classified into three subgroups on the basis of their duration of diabetes: Group 1A (n = 15) ≤3 years, Group 1B (n = 19) 3 to 5 years, and Group 1C (n = 16) >5 years. The inclusion criteria were no prior use of antihypertensive agents; blood pressure <130/85 mmHg; urinary albumin excretion <30 mg/day; and absence of renal failure, diabetietes, and hypertensive retinopathy. A total of 30 healthy individuals (16 female) (Group 2) were assessed as the control group. Systolic and diastolic blood pressures, HbA1c, body mass index, 24-h microalbuminuria (MAU), and NAG measurements in urine samples were performed by using colorimetric assay method in an analyzer (Roche Cobas Mira). The assay defined as fragmentation of 3-cresolsulfonphthaleinyl-N-acetyl-β-D-glucosaminide molecule by NAG to 3-cresolsulphonphthalein and N-acetylglucosamine molecules and serum creatinine were measured in all groups. Type II diabetic patients were administered perindopril (2 mg)/indapamide (0.625 mg) combination once daily for 4 months, and urinary NAG levels were measured at the end of treatment. Results. Statistically significant differences were observed between the groups 1 and 2 with respect to the levels of NAG and HbA1c (p < 0.05). In the treatment group, NAG levels decreased significantly (p < 0.05), whereas blood pressure and HbA1c levels did not change significantly (p > 0.05). In diabetic patients, pretreatment NAG were lowest in Group 1A and highest in Group 1C, although the difference between the treatment subgroups was not statistically significant (p > 0.05). Conclusion. Urinary NAG excretion is elevated in type II diabetic patients as compared with the healthy individuals. Perindopril/indapamide administration is effective in reducing urinary NAG excretion in these patients, and this effect seems to be independent from blood pressure and glycemia control. Presence of tubular proteinuria may be an early indicator of diabetic renal disease in patients without microalbuminuria. Perindopril (2 mg)/indapamide (0.625 mg)/o.d. treatment may have beneficial effect on the tubulointerstitial damage in diabetic kidney disease.

Activity of beta-N-acetylglucosaminidase in chronic alcoholic liver disease

Serum N-acetyl-B-glucosaminidase (NAG) activity was determined in a control group of 76 normal people and in 23 patients with hepatic cirrhosis: 15 non-compensated patients and 8 with compensated chronic liver fibrosis. NAG is significantly increased in the non-compensated group--mean value of 931.67 units vs 637.71 units for the controls (p less than 0.001). There is no significant elevation regarding the compensated group. No significant correlations were observed between NAG activity and hepatic functional tests. In the follow-up of the non-compensated group, NAG activity returned to normal with the clinical improvement; in 7 cases where this goal was not achieved there was elevation of NAG activity, with higher values in photo-systemic encephalopathy.

Reduced ability to clear ultrafilterable platinum with repeated courses of cisplatin.

Ultrafilterable plasma and urinary levels of platinum were quantitated for 24 hours after the first- and fourth-course infusion of cisplatin (CDDP) to seven patients. Four patients received 80 mg/m2 and three patients received 100 mg/m2 CDDP as a 2-hour infusion. The area under the curve (AUC) of ultrafilterable platinum, average renal clearance (CIR) of ultrafilterable platinum, and percentage of the platinum dose excreted in urine (% E) were determined for each infusion over the 26-hour period of the study. The AUC was higher in all patients after the fourth-course infusion, with a median increase of 74%. The median CLR was 494 mL/min (range, 214 to 996 mL/min) for the first course and decreased to 156 mL/min (range, 108 to 271 mL/min) for the fourth-course infusion (P less than .02). The median % E was 29.2% (range, 19.6% to 37.7%) for the first course and decreased to 19.9% (range, 12.4% to 25.9%) for the fourth-course infusion (P less than .02). There was no difference in creatinine clearance for the two infusions (median, 94 mL/min; P greater than .05). Urinary excretion of B2-microglobulin (B2-MG) and N-acetyl-B-glucosaminidase (NAG) was highly variable between patients and did not provide a useful predictor of changes in renal function. Four courses of CDDP therapy resulted in significantly reduced renal elimination of platinum in patients, probably through a reduction in the secretion of the drug in the proximal tubule of the kidney. The results suggest that increased antitumor effect and toxicity could occur in patients receiving sequential courses of cisplatin.

Does sucrose damage kidneys?

There is evidence to suggest that sucrose ingestion can cause renal parenchymal changes as well as increasing the urinary saturation index for calcium oxalate. Ten stone formers and 10 normal subjects received 250 gm of sucrose daily over a period of 7 days. Observations on the risk factors for calcium stone formation and urinary N-acetyl-B-glucosaminidase (NAG), a marker of renal tubular cell damage, were made. Oxalate excretion increased. Urinary calcium levels were unchanged but the pattern of response was different between the two groups, as with magnesium and phosphate. NAG was spontaneously higher in the patient group and increased significantly after sucrose ingestion in both groups.

Assessment of renal function during high-dose cis-platinum therapy in patients with ovarian carcinoma.

Five courses of cis-dichlorodiammine platinum (II) (100 mg/m2) were given to 22 patients with advanced stage III and IV ovarian cancer. Renal function was assessed by measurement of creatinine clearance, urinary osmolality and urinary B2-microglobulin (B2MG) in all patients, and by urinary alanine aminopeptidase (AAP) and N-acetyl-B-glucosaminidase (NAG) excretion in seven patients. Serum creatinine, creatinine clearance, urinary osmolality, and urinary B2-microglobulin were within the reference ranges and did not change significantly after five courses of cis-platinum in any patient. There was a significant increase in the urinary excretion of both enzymes (AAP and NAG) within 2 days of cis-platinum administration (NAG P less than 0.05 and AAP P less than 0.07). There was evidence of a cumulative effect during treatment for AAP (P less than 0.025).