Estimating the glomerular filtration rate and tubular dysfunction in an elderly population with normoalbuminuria in China.

BACKGROUND: The prevalence and clinical risk factors of normoalbuminuric renal impairment have not yet been investigated in elderly Chinese populations. To clarify this, we conducted survey research on an elderly Chinese community population. METHODS: A total of 691 elderly community participants were included in this study. Normoalbuminuria was defined as a urinary albumin to creatinine ratio (ACR) <30 mg/g in morning urine. The estimated glomerular filtration rate (eGFR) and urinary alpha-1-microglobulin to creatinine ratio (MCR) were evaluated to assess normoalbuminuric kidney impairment in this elderly population. RESULTS: Among the whole cohort, 30.25% had albuminuria, 8.68% showed reduced eGFR and 49.78% had increased MCR. Normoalbuminuric subjects also showed a high prevalence of low eGFR and increased MCR (6.02% for reduced eGFR and 37.55% for increased MCR). Among the normoalbuminuric participants, the highest prevalence of increased MCR was found in the subjects with diabetes (50%), whereas the highest prevalence of low eGFR was found in women (8.11%). There was no significant difference in ln-MCR values between normoalbuminuric subjects with eGFR>60 and < 60 ml/min/1.73 m2. Age, gender, diabetes and hypertension were all independent risk factors of increased MCR. Diabetes and hypertension showed no statistical influence on decreased eGFR,whereas gender carried the highest risk for reduced eGFR. CONCLUSIONS: Albuminuria may have limited utility as a screening marker of renal injury, as a considerable proportion of the elderly population have renal impairment despite normoalbuminuria. Rather than focusing solely on patients with diabetes or hypertension, normoalbuminuric renal impairment should be given more attention within the overall elderly population.

The synthesized transporter K16APoE enabled the therapeutic HAYED peptide to cross the blood-brain barrier and remove excess iron and radicals in the brain, thus easing Alzheimer's disease.

Alzheimer's disease (AD) is currently incurable and places a large burden on the caregivers of AD patients. In the AD brain, iron is abundant, catalyzing free radicals and impairing neurons. The blood-brain barrier hampers antidementia drug delivery via circulation to the brain, which limits the therapeutic effects of drugs. Here, according to the method described by Gobinda, we synthesized a 16 lysine (K) residue-linked low-density lipoprotein receptor-related protein (LRP)-binding amino acid segment of apolipoprotein E (K16APoE). By mixing this protein with our designed therapeutic peptide HAYED, we successfully transported HAYED into an AD model mouse brain, and the peptide scavenged excess iron and radicals and decreased the necrosis of neurons, thus easing AD.

Using the synthesized peptide HAYED (5) to protect the brain against iron catalyzed radical attack in a naturally senescence Kunming mouse model.

Alzheimer's disease (AD) is a progressive neurodegenerative disease of the brain. It cannot be cured currently, and those suffering from AD place a great burden on their caregivers and society. AD is characterized by high levels of iron ions in the brain, which catalyze radicals that damage the neurons. Knowing that the Aß42 peptide precipitates iron by binding iron ions at amino acid residues D1, E3, H11, H13, and H14, we synthesized a 5-repeat (HAYED) sequence peptide. By treating iron-stressed SH-SY5Y cells with it and injecting it into the cerebrospinal fluid (CSF) of naturally senescence Kunming mouse, which displaying AD-similar symptoms such as learning and memory dysfunction, neuron degeneration and high level of iron in brain, we found that HAYED (5) decreased the iron and radical levels in the cell culture medium and in the CSF. Specially, the synthesized peptide prevented cell and brain damage. Furthermore, functional magnetic resonance imaging (fMRI), Morris water maze and passive avoidance tests demonstrated that the peptide ameliorated brain blood-oxygen metabolism and slowed cognitive loss in the experimental senescence mice, and clinical and blood tests showed that HAYED (5) was innoxious to the kidney, the liver and blood and offset the AD-associated inflammation and anemia.