Oxalate Levels Research Articles

Higher inositol phosphates and total oxalate of cookies containing fruit by‐products and their influence on calcium, iron, and zinc bioavailability by Caco‐2 cells

AbstractBackground and objectivesFruit by‐products have been used as a strategy to increase the mineral content of cookies. However, to admit functionality in the organism, these minerals must be bioavailable. Therefore, this study aimed to evaluate the effect on the mineral bioavailability (calcium, iron, and zinc) of cookies prepared with partial replacement of wheat flour by fruit by‐products (melon peel, apple endocarp, and pineapple central axis).FindingsCookies containing fruit by‐products presented lower levels of phytate and oxalate when compared to the control. The use of pineapple by‐product in cookies increased zinc retention (26.40%). Cookies containing melon by‐product presented a higher uptake for iron (2.14%). Cookies with apple by‐product demonstrated the highest transport (0.06% and 9.71%) and uptake (2.92% and 15.52%) efficiencies for calcium and zinc, respectively.ConclusionsThe use of fruit by‐products in cookie formulations was associated with an improvement in the mineral bioavailability, which may represent nutritional and functional benefits for this foodstuff.Significance and noveltyAlthough some studies contemplate the use of fruit by‐products to increase the mineral content of cookies, the determination of their antinutrients and the effects on the mineral bioavailability measured by Caco‐2 cells are not widely explored in the literature.

PD12-01 ASSOCIATION OF OBESITY WITH INCREASED ENDOGENOUS OXALATE SYNTHESIS

INTRODUCTION AND OBJECTIVES:Urinary oxalate levels are affected by both dietary and endogenous components. Prior studies have demonstrated the positive correlation between weight/body mass index (B...

The Role of Different Nitrogen Sources Combined with Foliar Applications of Molybdenum, Selenium or Sucrose in Improving Growth and Quality of Edible Parts of Spinach (Spinacia oleracea L.)

Two pots experiments, at two successive winter seasons, were carried out to investigate the effects of two nitrogen (N) sources (ammonium nitrate and urea) and foliar applications of molybdenum (Mo), sucrose (Suc) or selenium (Se) on the growth and quality of the edible parts of spinach (Spinacia oleracea L. cv. Balady). The results indicated that the growth and quality of spinach plants can be greatly determined by the applied N source. The edible parts of spinach plants that received urea as N source showed lower content of NO3-, soluble oxalate, insoluble oxalate and total oxalate plus higher level of P content, however, higher moisture content as well as lower accumulation of dry mass, vitamin C and Fe were also observed in both seasons. Among the tested foliar applications at different concentrations, the treatment with 10% sucrose showed superior effects for increasing spinach growth (increase fresh weight, dry weight and leaves area) and quality (increase the contents of N, P, K, Ca, Fe, total protein and chlorophyll, as well as decreasing the contents of soluble oxalate and total oxalate) relative to the control (distilled water) in both seasons. The interaction treatment of urea fertilizer with foliar application of 10% sucrose was the most efficient one in decreasing NO3- and soluble oxalate contents without reductions in growth (fresh and dry weights), the contents of vitamin C and minerals against the corresponding control in both seasons.

Prevention of Complications in Patients with Urolithiasis on the Background of Type 2 Diabetes Mellitus After Extracorporeal Shock Wave Lithotripsy and Contact Ureterolithotripsy

The objective: to evaluate the results of complex treatment of patients with urolithiasis in patients with concomitant type 2 diabetes mellitus after extracorporeal shock wave lithotripsy and ureterolithotripsy.Materials and methods. We examined 60 patients with ureteral stones and concomitant type 2 diabetes mellitus after extracorporeal shock wave lithotripsy and ureterolithotripsy. Patients according to the prescribed postoperative therapy were divided into two groups of studies. The control group (n=28) was given classical therapy, and the main group (n=32) was additionally prescribed Solidagoren® phytopreparation at a dose of 30 drops 3 times a day for 3 months.Results. The levels of uric acid in the blood and urine, the level of urinary oxalates, the functional state of the kidneys before and after treatment, the dynamics of the discharge of residual concrements were evaluated.Conclusion. It is established that the components that make up Solidagoren reduce stone formation by reducing uricemia and increasing the excretion of oxalates. The use of the drug has a lithokinetic effect, as evidenced by a more rapid discharge of calculi and their fragments after endoscopic interventions and ESWL, helps to restore the functional state of the kidneys due to antioxidant properties, and vegetable origin determines its safe use.

Selective recovery of ferrous oxalate and removal of arsenic and other metals from soil-washing wastewater using a reduction reaction

Oxalic acid can effectively extract arsenic bound to amorphous iron oxides via dissolution of iron oxides containing arsenic. Therefore, soil washing with oxalic acid is a promising method to remediate arsenic-contaminated soil, since arsenic is often associated with amorphous iron oxides in soil. However, high cost of oxalic acid compared to the other inorganic acids commonly used for remediation of metal-contaminated soils is the main disadvantage of using oxalic acid for soil washing. In this study, in order to increase the economic feasibility of soil washing using oxalic acid, selective recovery of iron and oxalate as resources was suggested via two step reduction reaction using dithionite as a reductant during soil-washing wastewater treatment. In the first step, high levels of oxalate and iron present in wastewater was recovered as a ferrous oxalate phase. Under mild reducing conditions, ferric iron in the wastewater was reduced to ferrous iron, which could form a complex with oxalate and precipitate as the ferrous oxalate phase with low solubility. The ferrous oxalate phase did not affect dissolved arsenic retention in this step. The recovered ferrous oxalate phase can be applied in the industry as useful resources, which can contribute to the sustainable development and cleaner production. In the second step, arsenic in wastewater was removed by forming a realgar-like phase from the reaction with dithionite. Sulfide produced by the decomposition of dithionite reacted with arsenic and other metals in wastewater, and formed sulfide phases such as realgar (As4S4)/orpiment (As2S3) and lead sulfide (PbS).

Biochemical Risk Factors for Kidney Stones in Diabetic Patients

Objective: The aim of this study is to investigate the biochemical risk factors of kidney stones in diabetes. This includes the estimation of serum and urinary creatinine (Cr), albumin (Alb), sodium (Na+), potassium (K+), magnesium (Mg++), phosphorous (Po4++), calcium (Ca++), uric Acid (U.A), alkaline phosphatase (ALP), serum parathyroid hormone (PTH), reduced glutathione levels(GSH), urinary Oxalate, as well as citrate and nitric oxide (NO) levels were measured. Subjects and Methods: The clinical study was performed on 100 patients that attended Suez Health Insurance Organization and Ain Elhyah Hospital. Patients were divided into four groups; 25 diabetic patients (D) (mean age 52); 25 renal stone patients (R, S) (mean age 49); 25 diabetic renal stone patients (D R S)(mean age 51) and 25 control subjects (C)((mean age 47) age-matched, randomly selected. Blood and urine 24 hr samples were collected. Results: Serum (Cr) and (Alb) levels showed a non-significant changes in all patients. However, the data showed a significant decrease in (Mg++) level of all patients groups, with a significant level in (D R S) than (D) and (R, S) patients. Moreover, a significant increase in (U.A) levels of all patients groups but higher in (DRS) than (D) and (R, S) patients groups, the data revealed a significant decrease in urinary magnesium level in(DRS) patients group compared to (C), (R, S) and (D) patients groups. Moreover, a significant increase in urinary (U.A) level of all patients was noticed, it was significantly higher level in (DRS) than (R, S) patients groups. Oxalate level in all patients was increased, significantly. Meanwhile, the oxalate level was increased in (DRS) compared to (R, S) and (D) patients groups. The citrate level was decreased significantly in the urine of all patients groups with a significantly lower level of (DRS) than (R, S) and (D) patients groups. On other hand, a significant decrease in blood GSH level of all patients groups was observed where; its level in (DRS) was significantly lower than the (R, S) patients groups. However, data revealed a significant increase in serum (PTH) level of the (R, S) and (D R S) patients groups compared to (C) one. PTH level in (R, S) patients group was significantly higher than (D) and (DRS) patients groups. The data revealed a significant increase in serum ALP level of (D) and (D R S) groups compared to (C) group with a higher significant level in (DRS) than (R,S) patients groups. Moreover, the urinary 24h (NO) level was increased significantly in all patients groups compared to (C) group.

Oxalic acid content and pharmacobotany study of the leaf blades of two species of Annona (Annonaceae)

Annona muricata L. and A. squamosa L. are species of the Annonaceae family widely used in traditional medicine in Brazil for the treatment of noncommunicable diseases. However, this species may contain, for example, calcium oxalate crystals, that can precipitate in the kidneys and contribute to the formation of kidney stones. There are still few studies on the content of oxalic acid present in medicinal species. Thus, the objective of this work was to conduct a comparative anatomical and histochemical study between the species and determining its content of oxalic acid. Semipermanent histological slides were prepared, following common plant anatomy procedures, for analysis of the leaf blades in optical microscopy, polarization and scanning electron microscopy coupled with energy-dispersive X-ray spectrometry. To determine the total, soluble and insoluble oxalate content was used titration with potassium permanganate. The anatomical characterization allowed identifying the characters useful in the differentiation of the species and the druses. The histochemistry revealed the location of the metabolites and, along with the chemical microanalyses, demonstrated that the druses are of calcium oxalate. Annona squamosa presented the highest level of total oxalate. The study assists in the quality control of A. muricata and A. squamosa and brings new information on its oxalic acid content.

Fecal transplant modifies urine chemistry risk factors for urinary stone disease.

Urinary stone disease (USD) is a major health concern. There is a need for new treatment modalities. Recently, our group provided evidence for an association between the GMB composition and USD. The accessibility of the Gut Microbiome (GMB) makes it an attractive target for investigation and therefore, in these studies we have evaluated the extent to which the whole gut microbial community in fecal transplants can affect urinary stone risk parameters in an animal model. Fresh fecal pellets were collected from Zucker lean rats, homogenized in PBS (100 mg/mL), filtered through a 70 μm strainer and then orally gavaged into C57BL/6NTac germ‐free mice. Twenty‐four hours urine collections and GMB analysis were performed over time for 1 month. Kidney and gut tissue were harvested from transplanted mice for western blot analysis of expression levels of the Slc26a6 transporter involved in oxalate balance. Urinary calcium decreased after fecal transplant by 55% (P < 0.001). Urinary oxalate levels were on average 24% lower than baseline levels (P < 0.001). Clostridiaceae family was negatively correlated with urinary oxalate at 4 weeks after transplant (r = −0.83, P < 0.01). There was a 0.6 unit average increase in urinary pH from a baseline of 5.85 (SE ± 0.028) to 6.49 (SE ± 0.04) (P < 0.001) after transplant. There was a concomitant 29% increase in gastrointestinal alkali absorption (P < 0.001) 4‐weeks after fecal transplant. Slc26a6 expression increased by 90% in the cecum after transplant. Our results suggest that the gut microbiome may impact metabolism, alters urinary chemistry, and thereby may influence USD; the accessibility of the GMB can potentially be leveraged for therapeutic interventions.

Systemic Alanine Glyoxylate Aminotransferase mRNA Improves Glyoxylate Metabolism in a Mouse Model of Primary Hyperoxaluria Type 1.

Primary Hyperoxaluria Type 1 (PH1) is an autosomal recessive disorder of glyoxylate metabolism. Loss of alanine glyoxylate aminotransferase (AGT) function to convert intermediate metabolite glyoxylate to glycine causes the accumulation and reduction of glyoxylate to glycolate, which eventually is oxidized to oxalate. Excess oxalate in PH1 patients leads to the formation and deposition of calcium oxalate crystals in the kidney and urinary tract. Oxalate crystal deposition causes a decline in renal function, systemic oxalosis, and eventually end-stage renal disease and premature death. mRNA-based therapies are a new class of drugs that work by replacing the missing enzyme. mRNA encoding AGT has the potential to restore normal glyoxylate to glycine metabolism, thus preventing the buildup of calcium oxalate in various organs. Panels of codon-optimized AGT mRNA constructs were screened in vitro and in wild-type mice for the production of a functional AGT enzyme. Two human constructs, wild-type and engineered AGT (RHEAM), were tested in Agxt-/- mice. Repeat dosing in Agxt-/- mice resulted in a 40% reduction in urinary oxalate, suggesting therapeutic benefit. These studies suggest that mRNA encoding AGT led to increased expression and activity of the AGT enzyme in liver that translated into decrease in urinary oxalate levels. Taken together, our data indicate that AGT mRNA may have the potential to be developed into a therapeutic for PH1.

Biochemical urinalysis of healthy kidney and stone-generating kidney in unilateral urolithiasis

Introduction: Oxalate, calcium, uric acid, and citrate are among the most widely known biochemical factors for urinary stone formation. In most cases, urolithiasis occurs as unilateral despite the role of systemic metabolic factors in kidney stone formation. Objectives: The present research aimed to compare these urinary biochemical factors in healthy and stone-generating kidneys in patients with unilateral urolithiasis. Patients and Methods: Forty patients with unilateral urolithiasis participated in this cross-sectional, descriptive-analytical study. The patients were hospitalized in kidney surgery and kidney urology ward of Kashani hospital of Shahrekord, southwest Iran. After the implementation of crushing stone using transurethral lithotripsy (TUL), 5-10 cc of urinary sample was collected from each kidney. An AutoAnalyzer (Mindray Company, Bs–360 model) and laboratory kits (Bionic Company) were used to measure calcium, uric acid, and creatinine. Moreover, a manual method and Darman Faraz Kave company kits were applied to measure the levels of oxalate and citrate. Results on the healthy and stone-generating kidneys of each patient were separately analyzed using the Stata 13 software. Results: The difference in the mean ratio of uric acid, oxalate, and citrate to creatinine in the healthy kidneys and stone-generating kidneys was not significant. However, the mean UCa/UCr ratio in the healthy kidneys was 0.27±0.07 and relatively greater than that in the stone-generating kidneys (0.11±0.04) (P=0.06). Conclusion: The studied topical factors and secretory disorders had not any significant relationship with unilateral urolithiasis. The cause of unilateral urolithiasis should be searched in other factors such as metabolic factors, main positions of individual during 24 hours and sleeping, and anatomic disorders of kidney stone, or multifactorial.

Does the Urinary Calcium/Citrate Ratio Add to the Diagnostic Workup of Children at Risk of Kidney Stones? A Cross-Sectional Study

The purpose of the study was to evaluate urinary citrate/creatinine (UCi/UCr) and urinary calcium/citrate (UCa/UCi) ratios for distinguishing stone formers (SF) from non-stone formers (NSF) in an at-risk population. This was a retrospective study that included all pediatric patients who underwent urinary citrate testing from April 2017 to March 2018. The urinary levels of citrate, calcium, sodium, potassium, creatinine, oxalate, urate, pH, and specific gravity (SG) were measured in our clinical laboratory. Diagnosis of kidney stones was obtained through chart review.A total of 97 patients were included (46 NSF and 51 SF). The UCi/UCr ratio was not significantly different between NSF and SF. Median UCa/UCr ratio was higher in SF (0.67) compared with NSF (0.21, p &lt; 0.0001). The median ratio of UCa/UCi was also higher in SF (1.30) than in NSF (0.65, p = 0.001). Oxalate, urate, pH, SG, and urinary sodium/potassium ratio did not differentiate between the SF and NSF. Positive correlation was seen between UCa/UCr and urinary sodium/creatinine UNa/UCr (p &lt; 0.0001), as well as between UCa/UCr and UCi/UCr (p &lt; 0.0001).The study has demonstrated significantly higher UCa/UCi and UCa/UCr in SF compared with NSF, while the use of urinary oxalate, urate, pH, and SG did not differentiate between SF from NSF. We also confirmed a positive correlation between UNa/UCr and UCa/UCr. While the utility of UCa/UCr is well established, our data suggest that UCa/UCi rather than UCi/UCr may be more predictive in the clinical setting when evaluating for nephrolithiasis.

Multidimensional Analysis of Urinary Stone Diseases in Pediatric Patients.

Objectives:Urinary tract stones are less common in children than in adults. Determining the etiology is the most important step to achieve successful treatment and prevent future recurrence. The aim of this study was to investigate the clinical characteristics and possible risk factors for urinary stone disease in pediatric patients.Methods:The data of 126 patients with urinary stone disease who were treated in a pediatric nephrology clinic between 2000 and 2014 were analyzed retrospectively. A total 126 patients were enrolled in the study: 70 (55%) male and 56 (45%) female patients were included. The complaints, age of diagnosis, family histories, and stone location were examined. Direct urine microscopic examination, complete urinalysis, and urine culture were performed for all of the patients. Calcium, uric acid, oxalate, citrate, magnesium, and cystine levels were measured in urine collected in a 24-hour period. Serum electrolyte, blood urea nitrogen, creatinine, calcium, phosphorus, uric acid, and albumin levels were measured. Urinary ultrasound was performed. Stone analysis was conducted using the X-ray diffraction method. The mean age of the patients was 55 months (range: 1-162 months) at presentation.Results:In all, 34% of the patients had a family history of urinary stone disease. The rate of previous urinary tract infection was 26%. It was determined that 34% of the patients had been taking vitamin D and 5% had been taking a high dose. Metabolic risk factors determined were: hypercalciuria in 41%, hypocitraturia in 30%, hyperoxaluria in 14%, hyperuricosuria in 10%, and cystinuria in 5%. Among the group, 81% of the patients had kidney stones, 6.5% had ureter stones, and 2.5% had bladder stones. Furthermore, it was determined that 45% of the stones were composed of calcium oxalate, 35% had calcium phosphate stones, 14.2% had uric acid stones, and 13.3% had cystine stones. In 52% of the cases, extracorporeal shock wave lithotripsy was performed, and 71% underwent surgical treatment.Conclusion:Metabolic evaluation and stone analysis should be performed to prevent future recurrences in children with urinary stone disease and lifelong follow-up should be emphasized.

Oxalate-enhanced solubility of lead (Pb) in the presence of phosphate: pH control on mineral precipitation.

Here we study the precipitation of lead (Pb)-phosphate minerals over the pH range of 4.0 to 8.0 with and without oxalate, a ubiquitous and abundant low-molecular-weight organic acid derived from plants and microorganisms in environmental matrices. In the aqueous Pb-phosphate systems, phosphate precipitated Pb efficiently, reducing the dissolved Pb concentration below 1 μM at all the tested pH values, with the minimum solubility of about 0.1 μM measured at the intermediate pH of 6.0. The measured dissolved Pb and free Pb2+ ion activity were not in agreement with predictions from generally-accepted solubility products of the Pb phosphate minerals, particularly hydroxypyromorphite [Pb5(PO4)3OH]. Discrepancies between our measured Pb phosphate solubility products and older reported values are attributed to non-ideal behavior of these minerals (incongruent dissolution) as well as uncertainties in stability constants for soluble Pb-phosphate ion pairs. The presence of equimolar levels of oxalate and phosphate resulted in up to 250-fold increase in Pb solubility at acidic pH and about a 4-fold increase at pH 7.0, due to the strong suppression of Pb phosphate precipitation by oxalate and formation of soluble Pb-oxalate complexes. At pH 4.0 and 5.0, Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) identified a Pb-oxalate mineral phase as the only precipitate despite the presence of phosphate; in the absence of oxalate, Pb hydrogen phosphate, PbHPO4, stably formed under these acidic conditions. At pH 6.0 and greater, FTIR and XRD data revealed that Pb-phosphate [Pb3(PO4)2], and hydroxypyromorphite [Pb5(PO4)3OH] to a lesser extent, were the predominant precipitates both in the absence and presence of oxalate. Therefore, oxalate did not strongly interfere with Pb-phosphate mineral formation at aqueous pH greater than 6.0 but oxalate controlled Pb solubility at acidic pH values.

Bioavailability of Iron and Related Components in Cooked Green Leafy Vegetables Consumed in Cameroon

Green leafy vegetables (GLVs) are a potential source of iron to combat iron deficiency in iron deficient population. The aim of this study was to determine the bioavailability of iron in seven species of leafy vegetables (Solanumscrabrun, Venonia amygdalina, Cucurbita maxima, Amarathus hybridus, Colococia esculenta, Solanum macrocarpon and Telfairia occidentalis) consumed in Bamenda, Cameroon. A survey was carried out in 70 households in Bamenda, Cameroon to determine methods of preparation of these green leafy vegetables. Iron, antinutrients and vitamin C levels were determined using standard methods and the bioavailability of iron was determined using an in vitro dialys ability method. The vegetables used for the study were cooked with the addition of tomatoes, peanuts, melon seeds and soybean seeds. The loss of iron in GLVs was as a result of dilution caused by addition of the principal ingredients. The V. amygdalina cooked with soybean contained the highest level of iron (128.28 mg/100g). The S. scrabrum cooked with tomatoes had the highest Total phenolic coumponds of 0.91 g/100g; the C. esculenta recorded the highest with values ranging between 0.14 - 0.35 g/100g; the C. maxima cooked with soybean recorded the highest oxalate level (6.46 g/100g); and the vegetables cooked with melon seeds recording the highest in phytatelevels (70 - 1.63 g/100g). Vitamin C levels were highest in the S. macrocarpon cooked with tomatoes (199.96 mg/100g). Iron bioavailability was highest in A. hybridus cooked with tomatoes (28.09%). The iron bioavailability negatively correlated with phytates and positively with vitamin C. GLV consumed in Bamenda are good sources of iron whose bioavailability can be improved by using tomatoes in cooking.

Generation of a mouse model of Primary Hyperoxaluria Type 1 via CRISPR/Cas9 mediated gene editing

Background: Primary Hyperoxaluria Type 1 (PH1) is an inborn error of metabolism caused by mutations in the AGXT gene, which encodes for the hepatocyte-specific enzyme alanine: glyoxylate aminotransferase (AGT). AGT catalyzes the conversion of glyoxylate to glycine in the peroxisome and prevents the build-up of oxalate which occurs in PH1. This causes nephrocalcinosis, systemic oxalosis, and end-stage renal disease. Liver transplant is currently the only curative treatment available. Although a mouse model has previously been generated, the severity of the reported disease phenotype varies, and a better understanding of the genotype-phenotype relationship in both the mouse model and human disease is needed. Methods: We developed an Agxt-/- mouse model using CRISPR/Cas9-mediated gene editing. We performed a natural history study and ethylene glycol (EG) challenge to evaluate the phenotype of this mouse. Results: Agxt-/- mice had elevated plasma glycolate, urine glycolate, and urine oxalate levels compared to Agxt+/+ mice. A small subset of Agxt-/- mice developed minimal nephrocalcinosis (1/8 at 12 weeks, 1/8 at 26 weeks, 0/8 at 39 weeks, and 3/7 at 52 weeks of age). When challenged with 0.7% or 1.2% EG in drinking water for 3 weeks, 2/10 Agxt-/- mice developed nephrocalcinosis. Agxt2mRNA and protein expression were unchanged between Agxt-/- and Agxt+/+ mice. Hydroxy acid oxidase 1(Hao1) messenger ribonucleic acid (mRNA) levels were unchanged, but the corresponding glycolate oxidase protein was increased in Agxt-/- mice. Conclusion: We have created an Agxt-/- mouse model which resembles much of the clinical phenotype of PH1 patients and will be a useful tool in developing novel therapies for this devastating disease.

Production of ugba cubes from fermented pentaclethramacrophylla seeds

This research was designed as an innovation in the use of ugba as a food condiment. Production of “ugba” cubes from fermented seeds of Pentaclethramacrophylla (“ugba”) was successfully carried out. Ugba seeds were dehulled after soaking overnight in warm water and shredded. Fermentation of the shredded “ugba” seeds was done using Bacillus subtilis pure culturedisolated from already fermented “ugba”. Initial microbial study of the unfermented “ugba” showed the presence of Bacillus, Enterobacter, Penicillium, Aspergillus and yeast species. The initial bacterial count of the unfermented seed was 1.4 x 105cfu/g. Microbial counts of the “ugba” seeds after three days fermentation showed a disappearance of other microbial species except Bacillus species which was up to 9.60 x 104cfu/g. The shredded and fermented ugbaseeds were later milled and formed into cubes in a mould and oven dried.Sodium benzoate was used as a preservative. There was a drastic reduction of microbial count from 9.60 x 104cfu/g to 4.80 x 104cfu/g in “ugba” cubes preserved with sodium benzoate. Proximate composition of the “ugba” cubes showed increased levels of carbohydrates, ash and fibre content and a reduction in moisture protein and fats. Toxicological analysis of Bacillus fermented ugba presented low levels of hydrocyanic acid and soluble oxalates when compared with the unfermented sample. An overall acceptability of the ugba cubes was rated very highly when sensory evaluation was tested. This study recommends the use of Bacillus subtilis fermented nutritionally rich ugba cubes as a new innovation that will promote its acceptability worldwide.Keywords: Ugba, fermentation, Bacillus subtilis, sodium benzoate

Protective potential of Angelica sinensis polysaccharide extract against ethylene glycol-induced calcium oxalate urolithiasis

Purpose: To evaluate a Angelica sinensis polysaccharide aqueous extract as a preventive agent in experimentally induced urolithiasis using in- vitro and vivo models. Material and methods: Angelica sinensis polysaccharide was investigated in vitro to determine its antilithiatic effects on the formation and morphology of calcium oxalate (CaOx) crystals and was analyzed in vivo to determine its ability to prevent CaOx urolithiasis in rats subjected to ethylene glycol-induced urolithiasis. Potassium citrate administration was used in the positive control group. The urolithiasis-related biochemical parameters were evaluated in the rats urine, serum and kidney homogenates. Kidney sections were subjected to histopathological and immunohistochemical analyses, and urolithiasis-related phospho-c-Jun NH2-terminal protein kinase and kidney injury molecule-1proteins were evaluated by Western blot analyses. Results: Angelica sinensis polysaccharide exhibited concentration-dependent inhibition of CaOx crystal formation. The in vitro assay revealed significant inhibition of crystal formation (6.99 ± 1.07) in the group treated with 4.0 mg/mL Angelica sinensis polysaccharide extract compared with the control group (58.38 ± 5.63; p < .05). In vivo, after treatment with ethylene glycol for 28 days, urinary oxidative stress, oxalate, creatinine, urea and urolithiasis-related protein were significantly increased (p < .05), except for serum oxidative stress (p > .05). The rats administered the extract of Angelica sinensis polysaccharide showed significantly decreased pathological change and CaOx deposition (p < .05) compared with the urolithiatic rats. Significantly reduced levels of urinary oxidative stress, oxalate, creatinine, urea and urolithiasis-related protein were observed in the Angelica sinensis polysaccharide treatment groups (p < .05) compared with the nephrolithic rats. Conclusion: The results presented here suggest that Angelica sinensis polysaccharide has the potential to inhibit CaOx crystallization in vitro and may present anti-urolithiatic effects in vivo.

Anatomy, histochemistry and oxalic acid content of the leaflets of Averrhoa bilimbi and Averrhoa carambola

Averrhoa bilimbi L. and A. carambola L., Oxalidaceae, are the only two species of the genus Averrhoa L. Their leaves are widely used in folk medicine as an adjuvant in the treatment of diabetes. Some species may contain, for example, calcium oxalate crystals, which may lead to risk in its use when there is predisposition of individuals with reduced renal activity. Therefore, there are still few studies on the content of oxalic acid present in them, highlighting the importance of this investigation. The objective of this work was to conduct a comparative anatomical and histochemical study between the species and determining its content of oxalic acid. Semipermanent histological slides were prepared, following common plant anatomy procedures, for analysis of the leaflets in optical microscopy, polarization and scanning electron microscopy coupled with energy-dispersive X-ray spectrometry. To determine the total, soluble and insoluble oxalate content was used titration with potassium permanganate. The anatomical characterization allowed identifying the characters useful in the differentiation of the species. The histochemistry revealed the location of the metabolites. Chemical microanalyses demonstrated that the crystals are of calcium oxalate. A. carambola presented the highest levels of total oxalate and soluble oxalate. The study assists in the identification and quality control of A. bilimbi and A. carambola and brings new data on its oxalic acid content, which are important, in view of the medicinal use of the species.

Maize Oxalyl-CoA Decarboxylase1 Degrades Oxalate and Affects the Seed Metabolome and Nutritional Quality.

The organic acid oxalate occurs in microbes, animals, and plants; however, excessive oxalate accumulation in vivo is toxic to cell growth and decreases the nutritional quality of certain vegetables. However, the enzymes and functions required for oxalate degradation in plants remain largely unknown. Here, we report the cloning of a maize (Zea mays) opaque endosperm mutant that encodes oxalyl-CoA decarboxylase1 (EC4.1.1.8; OCD1). Ocd1 is generally expressed and is specifically induced by oxalate. The ocd1 mutant seeds contain a significantly higher level of oxalate than the wild type, indicating that the ocd1 mutants have a defect in oxalate catabolism. The maize classic mutant opaque7 (o7) was initially cloned for its high lysine trait, although the gene function was not understood until its homolog in Arabidopsis thaliana was found to encode an oxalyl-CoA synthetase (EC 6.2.1.8), which ligates oxalate and CoA to form oxalyl-CoA. Our enzymatic analysis showed that ZmOCD1 catalyzes oxalyl-CoA, the product of O7, into formyl-CoA and CO2 for degradation. Mutations in ocd1 caused dramatic alterations in the metabolome in the endosperm. Our findings demonstrate that ZmOCD1 acts downstream of O7 in oxalate degradation and affects endosperm development, the metabolome, and nutritional quality in maize seeds.

Therapeutic effects of aerial parts of Smyrnium cordifolium ethanolic extract on ethylene glycol-induced kidney calculi in rats

Introduction: In this study, the effects of the ethanolic extract of aerial parts (stem and leaves) of Smyrnium cordifolium (S. cordifolium) Boiss on the ethylene glycol(EG)-induced kidney calculi in rats was investigated. Materials and methods: Thirty-six male Wistar albino rats were randomly divided in 6 groups. Group I (normal control), Groups II (control of EG) to VI received EG 1% v/v in water for 28 days. Animals in Groups III and IV (preventive groups) received ethanolic extract of stem and leaves of S. cordifolium in 200 mg/kg and 400 mg/kg orally in water for 28 days, respectively. Groups V and VI (treatment groups) received extract in 200 mg/kg and 400 mg/kg orally in water from 15th to 28th day, respectively. Results: Results showed that the level of urine oxalate, blood urea and creatinine in EG group vs. normal control significantly increased (P<0.001). Extract did not show significant effect on urinary oxalate, urine volume and other blood biochemical parameters in the treatment groups (V and VI). Provision of extract resulted in significantly lower levels of urine oxalate and higher level of volume, serum creatinine and blood urea in III and IV groups as compared with Group II (P<0.05). Conclusion: These observations enable us to conclude that the ethanolic extract of aerial parts of S. cordifolium Boiss is effective against EG induced urinary calculi in rats.