Tissue-nonspecific Alkaline Phosphatase in Phosphate and Pyrophosphate Homeostasis.

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.

Recruitment Status

COMPLETED

Clinical Phase

NA

Total Enrollment

35 participants

Study Classification

INTERVENTIONAL

Study Start Date

2018-05-15

Study Completion Date

2019-09-06

Brief Summary

Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.

Vascular calcification is a common finding in chronic kidney disease and increases arterial stiffness leading to augmented cardiovascular morbidity. The calcification process is thoroughly regulated by pro and anticalcifying agents. The investigators hypothesize that imbalance in these compounds could depend on alkaline phosphatase activity. Therefore, the investigators will measure ALP activity, calcifications score, arterial stiffness and perform a bio-collection in monogenic rare diseases characterized by various levels of anticalcifying agents and in diverse CKD stages characterized by various levels of procalcifying compounds.

Related Clinical Trials

Explore similar clinical trials based on study characteristics and research focus.

Pyrophosphate and Arterial Calcification in Chronic Kidney Disease

NCT04950439

Chronic Kidney Diseases

RECRUITING NA

Study of Dietary Phosphate and Mineral Homeostasis in Early Chronic Kidney Disease

NCT00755690

Kidney Diseases

COMPLETED NA

Arterial Stiffness and Decreased Bone Buffering Capacity in Hemodialysis Patients

NCT00485706

Kidney Disease Hypercalcemia

COMPLETED NA

Effect of Phosphorus on Valvular and Vascular Calcification in ESRD

NCT03360331

Vascular Calcification

UNKNOWN

Low-Phosphate Diet and Fibroblast Growth Factor-23 Level

NCT03367338

Chronic Kidney Disease Requiring Chronic Dialysis Hyperphosphatemia Dietary Intervention +1 more

COMPLETED NA

Detailed Description

Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.

Chronic kidney disease (CKD) describes the gradual loss of kidney function from stage 1 (normal renal function) to stage 5 requiring maintenance dialysis or kidney transplantation (KT). Vascular calcification in CKD is a common finding and increases arterial stiffness leading to increased cardiovascular morbidity. The calcification process is the same for bones and arteries and is thoroughly regulated by pro and anticalcifying agents. Actually, inorganic phosphates (Pi) accelerate the calcification process and their levels are found increased in advanced CKD stage. In contrast, inorganic pyrophosphates (PPi) are potent anti-calcifying compounds resulting from the hydrolysis of extracellular ATP, but their role in CKD remains elusive. Tissue-nonspecific alkaline phosphatases (TNAP) convert PPi into Pi in calcification sites leading to hydroxyapatite deposition. The metabolism of PPi depends on diverse compounds, which are included in our bio-collection (Favre, Int J Mol Sci, 2017). The activity of plasma Alkaline Phosphatase (ALP) reflects the tissue production of TNAP. ALP activity is correlated to cardiovascular events in CKD patients. Preliminary results from our group show a stable plasma level of the PPi/Pi ratio independently from the glomerular filtration rate.

The investigators hypothesize that PPi/Pi imbalance could depend on ALP activity and could be a key determinant of vascular calcifications and arterial stiffness.

Therefore, the investigators will measure ALP activity, calcifications score, arterial stiffness and perform a bio-collection in monogenic rare diseases and in various CKD stages including hyperphosphatemic patients on maintenance hemodialysis.

Stage 1 and 2 CKD patients will be considered as a reference group because Pi levels and PPi levels are usually normal and calcification level is low. These patients will be compared to CKD patients with various Pi levels : low Pi levels in KT recipients 6 weeks after graft and high Pi levels in patients on maintenance dialysis. These patients (CKD 1 and 2) will be compared to patients with various PPi levels: patients with pseudoxanthoma elasticum (PXE) with low PPi levels and vascular calcifications and patients with hypophosphatasia (HPP) with high PPi levels and bone decalcification. PXE and HPP are rare monogenic disorder resulting from mutation in ABCC6 and the gene encoding TNAP respectively.

Conditions

See the medical conditions and disease areas that this research is targeting or investigating.

Chronic Kidney Disease

Study Design

Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.

Allocation Method

NON_RANDOMIZED

Intervention Model

PARALLEL

Primary Study Purpose

BASIC_SCIENCE

Blinding Strategy

NONE

Study Groups

Review each arm or cohort in the study, along with the interventions and objectives associated with them.

Chronic Kidney Disease

Blood and urinary samples on the following patients:

10 Stage 1 and 2 CKD patients 10 patients 6 weeks after graft 10 patients on maintenance dialysis.

Group Type OTHER

Blood samples

Intervention Type OTHER

Blood samples on an empty stomach

Urinary samples

Intervention Type OTHER

first urinary in the morning

Pseudoxanthoma elasticum (PXE)

Blood and urinary samples on the following patients:

10 patients with pseudoxanthoma elasticum (PXE) with low PPi levels and vascular calcifications and patients with hypophosphatasia (HPP) with high PPi levels and bone decalcification.

Group Type OTHER

Blood samples

Intervention Type OTHER

Blood samples on an empty stomach

Urinary samples

Intervention Type OTHER

first urinary in the morning

Hypophosphatasia (HPP)

Blood and urinary samples on the following patients:

4 patients with hypophosphatasia (HPP) with high PPi levels and bone decalcification.

Group Type OTHER

Blood samples

Intervention Type OTHER

Blood samples on an empty stomach

Urinary samples

Intervention Type OTHER

first urinary in the morning

Interventions

Learn about the drugs, procedures, or behavioral strategies being tested and how they are applied within this trial.

Blood samples

Blood samples on an empty stomach

Intervention Type OTHER

Urinary samples

first urinary in the morning

Intervention Type OTHER

Eligibility Criteria

Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.

Inclusion Criteria

* patient with Chronic kidney disease (stage 1 or 2, 6 weeks after graft or patients on maintenance dialysis) or patient with pseudoxanthoma elasticum or patient with hypophosphatasia
* informed consent signed