Effects and mechanisms of total flavones of Abelmoschus manihot in attenuating diabetic tubulopathy by targeting endoplasmic reticulum stress-induced cell apoptosis / 中国中药杂志

Renal tubular injury in patients with diabetic kidney disease(DKD) may be accompanied by glomerular and microvascular diseases. It plays a critical role in the progression of renal damage in DKD, and is now known as diabetic tubulopathy(DT). To explore the multi-targeted therapeutic effects and pharmacological mechanisms in vivo of total flavones of Abelmoschus manihot(TFA), an extract from traditional Chinese medicine for treating kidney disease, in attenuating DT, the authors randomly divided all rats into four groups: a normal control group(normal group), a DT model group(model group), a DT model+TFA-treated group(TFA group) and a DT model+rosiglitazone(ROS)-treated group(ROS group). The DT rat model was established based on the DKD rat model by means of integrated measures. After successful modeling, the rats in the four groups were continuously given double-distilled water, TFA suspension, and ROS suspension, respectively by gavage every day. After 6 weeks of treatment, all rats were sacrificed, and the samples of their urine, blood, and kidneys were collected. The effects of TFA and ROS on various indicators related to urine and blood biochemistry, renal tubular injury, renal tubular epithelial cell apoptosis and endoplasmic reticulum stress(ERS), as well as the activation of the protein kinase R-like endoplasmic reticulum kinase(PERK)-eukaryotic translation initiation factor 2α(eIF2α)-activating transcription factor 4(ATF4)-C/EBP homologous protein(CHOP) signaling pathway in the kidney of the DT model rats were investigated. The results indicated that hypertrophy of renal tubular epithelial cells, renal tubular hyperplasia and occlusion, as well as interstitial extracellular matrix and collagen deposition occurred in the DT model rats. Moreover, significant changes were found in the expression degree and the protein expression level of renal tubular injury markers. In addition, there was an abnormal increase in tubular urine proteins. After TFA or ROS treatment, urine protein, the characteristics of renal tubular injury, renal tubular epithelial cell apoptosis and ERS, as well as the activation of the PERK-eIF2α-ATF4-CHOP signaling pathway in the kidney of the DT model rats were improved to varying degrees. Therein, TFA was superior to ROS in affecting the pathological changes in renal tubule/interstitium. In short, with the DT model rats, this study demonstrated that TFA could attenuate DT by multiple targets through inhibiting renal tubular ERS-induced cell apoptosis in vivo, and its effect and mechanism were related to suppressing the activation of the PERK-eIF2α-ATF4-CHOP signaling pathway in the kidney. These findings provided preliminary pharmacological evidence for the application of TFA in the clinical treatment of DT.

Síndrome de Bartter: una tubulopatía infrecuente de inicio antenatal / Bartter syndrome: an infrequent tubulopathy of prenatal onset

INTRODUCCIÓN: Síndrome de Bartter (SB) es una tubulopatía hereditaria, poco frecuente que tiene dos formas de presentación, forma grave de inicio antenatal (Bartter neonatal) y forma de aparición más tardía (Bartter clásico). En su forma antenatal se manifiesta con poliuria fetal, polihidroamnios de inicio precoz y severo, parto prematuro secundario y restricción de crecimiento intrauterino. La etapa postnatal presenta episodios recurrentes de deshidratación y desbalance electrolítico que pue den comprometer la sobrevida del paciente. OBJETIVO: Comunicar un caso de SB neonatal y presentar una revisión de la literatura en esta patología. CASO CLÍNICO: Prematuro 35 semanas, con antecedente de severo polihidroamnios diagnosticado a las 27 semanas de gestación, sin causa aparente. Desde su nacimiento evolucionó con poliuria y alcalosis metabólica hipokalémica haciendo plantear, en primera semana de vida, diagnóstico de Síndrome de Bartter neonatal. El laboratorio confirmó per didas urinarias de electrólitos. Fue manejado con balance hídrico estricto y suplementación de sodio y potasio, logrando estabilizar peso y desbalance electrolítico. Se mantiene en control nefrológico, con suplementación de gluconato de potasio y cloruro de sodio. Se agregó ibuprofeno al cuarto mes como parte del tratamiento. Al séptimo mes de vida, ecografía renal demostró nefrocalcinosis. Al año de vida se evidenció hipoacusia sensorioneural profunda requiriendo implante coclear. CONCLUSIÓN: Presencia de polihidroamnios severo de aparición temprana sin causa identificada debe hacer sospechar SB, que aun siendo infrecuente determina graves alteraciones hidroelectrolíticas y debe ser iniciado su tratamiento precozmente.

INTRODUCTION: Bartter syndrome (BS) is a rare inherited tubulopathy that has two presentation forms, the first one is a severe form of antenatal onset (neonatal Bartter) and the second one is a later on set form during the first years of life (classic Bartter). In the antenatal form, it manifests with fetal polyuria, polyhydramnios of early and severe onset, premature delivery, and intrauterine growth restriction. In the postnatal stage, it presents recurrent episodes of dehydration and electrolyte im balance that can compromise the survival of the patient. OBJECTIVE: To report a clinical case of neo natal BS and a review of the literature. CLINICAL CASE: Premature newborn of 35 weeks of gestation with history of severe polyhydramnios diagnosed at 27 weeks of gestation, without apparent cause. From birth, the patient presented polyuria and hypokalemic metabolic alkalosis making a diagnosis of Neonatal Bartter Syndrome in the first week of life. Laboratory tests confirmed urinary electrolyte losses. The patient was treated with strict water balance and sodium and potassium supplementa tion, achieving weight and electrolyte imbalance stabilization. The patient remains in control in the nephrology unit, with potassium gluconate and sodium chloride supplementation. At the fourth month, ibuprofen was added as part of treatment. At the seventh month of life, renal ultrasound showed nephrocalcinosis. At one year of life, profound sensorineural hearing loss was observed re quiring a cochlear implant. CONCLUSION: The presence of severe polyhydramnios of early onset with no identified cause should lead to suspicion of neonatal BS which even when infrequent determines severe hydroelectrolytic alterations and should be treated early.

A novel heterozygous duplication of the SLC12A3 gene in two Gitelman syndrome pedigrees: indicating a founder effect

Gitelman syndrome is an autosomal recessive salt-wasting tubulopathy caused by mutations in the SLC12A3 gene. A female and a male sibling from two unrelated Greek-Cypriot families presenting with a severe salt-wasting tubulopathy dueto compound heterozygous mutations of a novel duplication and a previously reported missense mutation in the SLC12A gene are described. Sanger sequencing was used to identify possible mutations in the SLC12A3 gene. For the detection of duplications/conversions and deletions in the same gene, Multiplex ligation probe amplification (MLPA) analysis was performed. Direct sequencing and MLPA analysis of the SLC12A3 gene identified two compound heterozygous mutations in both unrelated probands. Both probands were identified to carry in compound heterozygosity the known p.Met581Lys and a novelheterozygous duplication of exons 9-14 (E9_E14dup). The diagnosis of Gitelman syndrome was made through clinical assessment, biochemical screening and genetic analysis. The identification of the novel SLC12A3 duplication seems to be characteristic of Greek-Cypriot patients and suggests a possible ancestral mutational event that has spread in Cyprus due to a possible founder effect. Testing for Gitelman syndrome probable variants can be performed before proceeding to a full gene sequencing dropping the diagnostic cost. In addition, this report adds to the mutational spectrum observed.

Asociación entre hallazgos bucales y enfermedad renal en pacientes pediátricos en Venezuela / Association between oral findings and renal disease among pediatric patients in Venezuela

La cavidad oral puede mostrar signos clínicos de enfermedades renales que pasan desapercibidos. El objetivo de este estudio fue evaluar la asociación entre defectos del esmalte (DDE), cálculo dental, bajo peso, baja talla y el diagnóstico de disfunciones tubulares simples o tubulopatías entre 256 pacientes pediátricos (160 con tubulopatías simples y 96 controles sanos) en un importante hospital urbano de Valencia, Venezuela. La frecuencia de DDE en el grupo con tubulopatías fue de 56.25% y en controles de 29.2%, cálculo dental 26.9% y 10.4%, respectivamente. Los modelos de regresión logística revelaron la presencia de DDE (p = 0.000), cálculo dental (p = 0.002), bajo peso (p = 0.000) y baja talla (p = 0.000); cada una de estas características por separado presentó una asociación estadísticamente significativa con tubulopatías. Los niños con DDE tienen 2.7 más posibilidades de afección renal que los que no presentan DDE (Wald = 11.263 y p-valor = 0.001), también los pacientes con cálculo dental son 2.3 veces más propensos a padecer tubulopatías que los que no lo tienen (Wald = 4.076 y p-valor = 0.043) y los niños con bajo peso tienen 53.7% más probabilidad de presentar disfunción tubular simple (Wald = 4.751 y p-valor = 0.029). De allí que se puede afi rmar que la ocurrencia de tubulopatías tiene una asociación estadísticamente significativa con la presencia de DDE, cálculo dental y bajo peso. Estos datos pueden contribuir a que en la consulta odontopediátrica se aumente el número de referencia de niños con tubulopatías por la asociación de las variables mencionadas (AU)

The oral cavity may show clinical signs of renal diseases that go unnoticed. The aim of this study was to evaluate the association between enamel dental defects (EDD), dental calculus, low weight, low height and the diagnosis of simple tubular dysfunctions or tubulopathies among 256 pediatric patients (160 with simple tubulopathies and 96 healthy controls) in an important urban hospital of Valencia, Venezuela. The frequency of EDD in the group with tubulopathies was 56.25% and in controls 29.2%, dental calculus 26.9%, and 10.4%, respectively. The logistic regression models re-vealed that the presence of DDE (p = 0.000), dental calculus (p = 0.002), low weight (p = 0.000) and low size (p = 0.000), each of these characteristics Patients presented a statistically signifi cant association with the presence of tubulopathies. Children with EDD are 2.7 times more likely to have renal disease than those without EDD (Wald = 11.263 and p-value = 0.001); patients with dental calculus are 2.3 times more likely to have tubulopathies than (Wald = 4.076 and p-value = 0.043) and children with low weight were 53.7% more likely to have simple tubular dysfunction (Wald = 4.751 and p-value = 0.029). Hence, it can be affi rmed that the occurrence of tubulopathies has a statistically signifi cant association with the presence of DDE, dental calculus, and low weight. These data may contribute to the increase in the reference number of children with tubulopathies by the association of the mentioned variables (AU)

Research advances in hypokalemic salt-losing tubulopathies / 上海交通大学学报（医学版）

Hereditary tubular disorders play an important role in the ion transport mechanism of kidney. Hypokalemic salt-losing tubulopathies (SLTs) are a set of rare hereditary diseases, which accompany with hypokalaemic metabolic alkalosis, normo or hypotension, and are associated with high plasma renin activity and hyperaldosteronemia. Bartter syndrome and Gitelman syndrome, characterized by the disability of the thick ascending limb of Henle's loop and/or the distal convoluted tubule, respectively, are two common types of SLTs. Some types of SLTs share similar clinical manifestations, making them difficult to diagnose. Besides, with the development of molecular genetics, new disease-causing genes have been discovered. It's inconvenient for clinicians to refer to the old classification of SLTs. The review mainly covered the newly discovered pathogenic genes of SLTs and the corresponding pathogenic mechanisms. In addition, a new system for classification of SLTs based on physiology and pharmacology was introduced.

Gitelman syndrome: From pathophysiology to clinical practice / 国际药学研究杂志

Normal tubular transport function is important for maintaining the volume of fluid and electrolyte in the body. Advances in molecular biology have revealed the genetic regulation and pathophysiological mechanisms of inherited tubular disorders. This progress not only sheds some light on the clinical practice, but also leads to better understanding of the normal tubular structures and function. As the most common inherited tubular disorders, Gitelman syndrome (GS) is an autosomal recessive inherited disease, mainly caused by loss-of-function mutations in the SLC12A3 gene encoding the sodium-chloride co-transporter (NCC) in the distal convoluted tubule. This review summarizes some of the recent progress in genetic diagnosis, in vivo and in vitro functional studies and management of GS.

Analysis of clinical and pathological manifestations of light chain proximal tubulopathy / 中华肾脏病杂志

Objective To investigate the clinical and pathological characteristics of light chain proximal tubulopathy (LCPT).Methods Nine patients with LCPT diagnosed by renal biopsy in Peking University First Hospital from January 1,2011 to September 30,2016 were enrolled,and their clinical findings and pathological features were reviewed.Immunofluorescence (IF) of light chains (κ,λ) on paraffin sections after protease digestion and immunogold labeling of light chains (κ,λ) on ultrathin sections were performed in some cases.Results The main clinical manifestation of the nine patients was proteinuria of small molecules,with acute or chronic renal insufficiency,and six of them led to partial or complete Fanconi syndrome (FS).The hematologic diseases included 3 cases of multiple myeloma and 6 cases of monoclonal gammopathy of renal significance (MGRS).Pathological examination of renal biopsy showed two types:crystalline and noncrystalline LCPT.Seven cases of crystalline LCPT were stained for κ light chain,the proximal tubular epithelial cytoplasm exhibited fine granular vacuolation,with needle-shaped crystals and clear clefts by light microscopy,the intracytoplasmic inclusions of various shapes including rhomboidal,rectangular and rod-shaped crystals were identified by electron microscopy.Two cases of noncrystalline LCPT were stained for λ light chain,the prominent argyrophilic granules in cytoplasm of proximal tubular epithelia were observed by light microscopy,and intracytoplasmic large and irregular shaped phagolysosomes were found by electron microscopy,cast nephropathy were coexisted in these 2 cases,the additional light chain deposition disease were confirmed in one of them by electron microscopy and IF.All cases had monotypic staining of light chains in cytoplasm of proximal tubules by IF on frozen tissue and paraffin sections after protease digestion,with the latter method being more sensitive than the routine IF.The immunogold labeling showed specific monotypic labeling of κ and λ light chain on intracytoplasmic crystals and phagolysosomes respectively by immunoelectron microscopy.Conclusions LCPT is a rarely reported entity that manifested as acquired Fanconi syndrome and dysfunction of proximal tubules clinically.Pathologically it is divided into two types:crystalline and noncrystalline LCPT,with more prevalent of κ light chain related crystalline type,noncrystalline LCPT is mostly λ type,and is easily coexisted with cast nephropathy.The IF and immunoelectron microscopy of light chains(κ,λ) and ultrastructural examination by electron microscopy are important methods for the diagnosis of LCPT.

Late Diagnosis of Fanconi-Bickel Syndrome: Challenges With the Diagnosis and Literature Review

Abstract Fanconi-Bickel syndrome (FBS), also known as glycogen storage disease type XI (GSD XI), is a rare autosomal recessive disorder of carbohydrate metabolism. It is caused by mutations in the gene SLC2A2, which encodes for the facilitative glucose transporter GLUT2. Diagnosis of FBS is often delayed since the clinical features and laboratory markers often overlap with other disorders whose characteristic features include short stature, fasting hypoglycemia, postprandial hyperglycemia, hepatomegaly, hypophosphatemic rickets, and proximal renal tubular dysfunction. In this article, we present a case of FBS and its management in an African American female who initially presented with persistent proximal tubulopathy, hypercalciuria, and metabolic acidosis. We also include a recent literature review on FBS and discuss other metabolic disorders that should be considered in the differential diagnosis.

Mutations in SLC12A3 and CLCNKB and Their Correlation with Clinical Phenotype in Patients with Gitelman and Gitelman-like Syndrome

Gitelman's syndrome (GS) is caused by loss-of-function mutations in SLC12A3 and characterized by hypokalemic metabolic alkalosis, hypocalciuria, and hypomagnesemia. Long-term prognosis and the role of gene diagnosis in GS are still unclear. To investigate genotype-phenotype correlation in GS and Gitelman-like syndrome, we enrolled 34 patients who showed hypokalemic metabolic alkalosis without secondary causes. Mutation analysis of SLC12A3 and CLCNKB was performed. Thirty-one patients had mutations in SLC12A3, 5 patients in CLCNKB, and 2 patients in both genes. There was no significant difference between male and female in clinical manifestations at the time of presentation, except for early onset of symptoms in males and more profound hypokalemia in females. We identified 10 novel mutations in SLC12A3 and 4 in CLCNKB. Compared with those with CLCNKB mutations, patients with SLC12A3 mutations were characterized by more consistent hypocalciuria and hypomagnesemia. Patients with 2 mutant SLC12A3 alleles, compared with those with 1 mutant allele, did not have more severe clinical and laboratory findings except for lower plasma magnesium concentrations. Male and female patients did not differ in their requirement for electrolyte replacements. Two patients with concomitant SLC12A3 and CLCNKB mutations had early-onset severe symptoms and showed different response to treatment. Hypocalciuria and hypomagnesemia are useful markers in differentiation of GS and classical Bartter's syndrome. Gender, genotypes or the number of SLC12A3 mutant alleles cannot predict the severity of disease or response to treatment.

Síndrome de Bartter: reporte de un caso y revisión de la literatura / Bartter syndrome: a case report and literature review / Síndrome de Bartter: relatório de um caso e revisão da literatura

Se presenta el caso de un lactante masculino de 14 meses de edad que consulta por vómito, astenia, adinamia y palidez generalizada. Ingresa con un peso de 5.4 kg y una talla de 69 cm, marcada disminución del panículo adiposo y de la masa muscular, sin edemas. Los análisis reportaron potasio sérico 2,02 mEq/L, cloro 89,4 mEq/L, sodio 134,5 mEq/L, magnesio 2,39 mg/dl, albumina 4,52 gr/dl, creatinina sérica 0,17 mg/dl, uroanálisis con proteinuria 75 mg/dl y ecografía renal normal. Se sospecha síndrome de Bartter, por lo que se solicitan gases venosos que muestran pH 7,519, pO2 60 mmHg, pCO2 32,5 mmHg, HCO3 25,8 mmol/l, BE 3,3 mmol/L, relación calcio/creatinina en orina: 0,056, aldosterona 11,9 ngr/dl y renina total 459 pg/ml. Con estos resultados se hace el diagnóstico de SB, siendo compatible con el tipo III. Se iniciaron suplementos de potasio y diuréticos ahorradores de potasio sin lograr un adecuado aumento del potasio sérico y solo hasta iniciar indometacina este se logra corregir,al igual que la adecuada ganancia pondoestatural. A continuación se hace una revisión de la literatura sobre el síndrome de Bartter...

A case of 14-month male infant presenting with vomit, asthenia, adynamia, and generalized paleness is presented. At admission, his weight is 5.4 kg and height 69 cm, with marked reduction of his adipose pannus and muscular mass, with no edema. The tests reported serum potassium 2.02 mEq/L, chlorine 89.4 mEq/L, sodium 134.5 mEq/L, magnesium 2.39 mg/ dl, albumin 4.52 gr/dl, serum creatinine 0.17 mg/dl, urinalysis with proteinuria 75 mg/dl, and a normal renal echography. Bartter syndrome was suspected reason why venous gases were ordered which showed pH 7.519, pO2 60 mmHg, pCO2 32,5 mmHg, HCO3 25.8 mmol/l, BE 3.3 mmol/L, urine calcium/creatinine ratio 0.056, aldosterone 11.9 ngr/dl and total renin 459 pg/ml. With these results, the patient was diagnosed with BS, being compatible with type III. Potassium supplements and potassium sparing diuretics were started without achieving a proper serum potassium increase and only after starting indomethacine it could be corrected as well as the appropriate pondostatural increase. Below, there is a literature review about the Bartter syndrome Bartter, tubulopathy, hypokalemia...

Apresenta-se o caso de um lactante masculino de 14 meses de idade que consulta por vômito, astenia, adinamia e palidez generalizada. Dá entrada com um peso de 5.4 kg e uma estatura de 69 cm, marcada diminuição do panículo adiposo e da massa muscular, sem edemas. Os exames mostraram potássio sérico 2,02 mEq/L, cloro 89,4 mEq/L, sódio 134,5 mEq/L, magnésio 2,39 mg/dl, albumina 4,52 gr/dl, creatina sérica 0,17 mg/dl, uroanálise com proteinúria 75 mg/dl e ecografia renal normal. Suspeita-se de síndrome de Bartter, por isso são solicitados gases venosos que mostram pH 7,519, pO2 60 mmHg, pCO2 32,5 mmHg, HCO3 25,8 mmol/l, BE 3,3 mmol/L, relação cálcio/ creatina na urina: 0,056, aldosterona 11,9 ngr/dl e renina total 459 pg/ml. Com estes resultados é feito o diagnóstico de SB, sendo compatível com o tipo III. Iniciaram-se suplementos de potássio e diuréticos economizadores de potássio sem obter-se um aumento adequado do potássio sérico, somente ao iniciar indometacina o mesmo é corrigido, da mesma forma que o adequado desenvolvimento pondoestatural. A seguir é feita uma revisão da literatura sobre a síndrome de Bartter...

Light microscopic and electron microscopic features of cyclosporine nephrotoxicity in rats

In order to clarify morphologic changes associated with cyclosporine (CS) nephrotoxicity, CS in ethyl alcohol at 25 mg/kg/day i.p. was administered to male Sprague-Dawley rats for periods of 1 to 8 weeks. Mean systolic BP was slightly increased in the CS group at 4 weeks (p < 0.05), but there was no difference compared to a control group at 8 weeks. Blood urea nitrogen was significantly elevated at 4 weeks and continued to rise (p < 0.005), whereas serum creatinine was elevated at 8 weeks. Microscopic examination of the kidneys from CS-treated rats at one week revealed cytoplasmic vacuolization in all segments of the proximal tubules, tubular inclusion bodies, and peritubular capillary congestion. Ultrastructurally, some vacuoles were neutral fat droplets, while others appeared as single membrane-bound structures due to dilatation of the endoplasmic reticulum. The tubular inclusion bodies were enlarged autolysosomes filled with distorted mitochondrial fragments. At two weeks, tubular regeneration was prominent, in addition to the above mentioned toxic tubulopathy. At four weeks, focal areas of interstitial fibrosis and tubular atrophy associated with cystic dilatation were seen. At 8 weeks, interstitial and intratubular microcalcification were present, in addition to patchy foci of interstitial fibrosis, but vascular lesions were not demonstrated. Although renal tubular changes characterized by vacuolization, inclusion bodies, and microcalcification and interstitial fibrosis are not specific for CS toxicity, these changes are commonly found in both humans and rats at high doses of CS.