Research Advances

JAMA: "Worldwide Preparedness for Kidney Health Care"

The Journal of the American Medical Association (JAMA) published an editorial by Sreedhar Mandayam, MD, MPH and Wolfgang C. Winkelmayer, MD, MPH, ScD commenting on a study completed about the level of preparedness for kidney care worldwide.

Sugar-Sweetened Drinks Linked to More than 180,000 Deaths Each Year

Researchers estimate that worldwide, 184,000 deaths per year are attributable to consumption of sugar-sweetened beverages (SSBs): 133,000 from diabetes, 45,000 from cardiovascular disease, and 6450 from cancers. Five percent of such deaths occurred in low-income, 70.9% in middle-income, and 24.1% in high-income countries. Proportional mortality due to SSB consumption ranged from <1% in Japanese >65 years old to 30% in Mexicans <45 years old, and 8.5 million disability-adjusted life years were related to SSB intake.

Program Seeks to Integrate Tissue Chips that Mimic Human Organ Functions

Researchers are working to refine 3-D human tissue chips and to combine them into an integrated system. Fifteen NIH institutes and centers are involved in coordinating the effort, which is called the Tissue Chip for Drug Screening program. One collaborative effort will share resources and expertise for the heart, blood vessel, and liver tissue chips.

Proteasome Inhibitor May Help Prevent Organ Rejection

A new study shows that bortezomib, a proteasome inhibitor that is already approved by the FDA for treatment of multiple myeloma, reduces HLA antibodies in patients with CKD to a greater extent than traditional methods employing intravenous immunoglobulin. A 51.5% reduction in immunodominant antibodies was observed at 28 days with bortezomib treatment (1.3 mg/m2) and reductions increased with higher bortezomib dosing densities. Nineteen out of 44 treated patients (43.2%) were transplanted with low acute rejection rates (18.8%) and donor-specific antibody formation (12.5%).

Small Changes in Blood Acidity May Affect CKD Patients’ Health

New research suggests very small changes in blood pH levels may affect renal calcium reabsorption and parathyroid hormone (PTH) secretion. In both human embryonic kidney cells and bovine parathyroid cells, decreasing the extracellular pH from 7.4 to 7.2 rapidly inhibited intracellular calcium mobilization through the calcium-sensing receptor, whereas raising extracellular pH to 7.6 increased responsiveness to extracellular calcium. Also, pH elevation suppressed PTH secretion from human parathyroid cells, while acidosis increased PTH secretion.

Cooler Temperatures Diminish the Body’s Immune Response against the Common Cold Virus

New research sheds light on why most rhinovirus strains, which cause the common cold, replicate better at the cooler temperatures found in the nasal cavity than at lung temperature. Investigators found that airway epithelial cells supporting rhinovirus replication initiate a more robust antiviral defense response at warmer temperatures. Airway cells with genetic deficiencies in interferon receptor signaling supported much higher levels of viral replication at 37°C.

Genetic Markers in Mice and Humans Linked with Obesity

By analyzing epigenetic markers, or chemical tags, at more than 7 million sites in the DNA of the fat cells in mice, researchers found clear differences between normal and obese mice—and they found a similar pattern in human cells. Some of the epigenetic changes associated with obesity affect genes already known to raise diabetes risk. Others affect genes that had not been conclusively linked to the disease, but that have roles in metabolism. Some of the genes regulate insulin action on sugar uptake, making them potential targets for treating type 2 diabetes.

Drug May Have Benefits for Sympathetic Nerve Activity, Arterial Stiffness in CKD

People with CKD often have an overactivation of the sympathetic nervous system, which contributes to increased risks for cardiovascular events. However, tetrahydrobiopterin may be able to dial back this process. In a randomized study of 36 patients with CKD, the drug had positive effects on the sympathetic nervous system and some measures of arterial stiffness.

Soil Screening Methods Uncover Potential New Antibiotic

New methods that extract drugs from soil bacteria have yielded a powerful new antibiotic, called teixobactin, that can cure severe gram-positive bacterial infections in mice with no adverse effects. Teixobactin inhibits cell wall synthesis by binding to a precursor of peptidoglycan and a precursor of cell wall teichoic acid. During their studies, investigators found no signs of any mutants of Staphylococcus aureus or Mycobacterium tuberculosis that became resistant to teixobactin.

Genetic Variations in Magnesium-Related Ion Channels May Affect Diabetes Risk

Interactions of diet, genetics, and ethnicity may affect magnesium-mediated diabetes risk, according to a new study. After identifying 17 magnesium-related ion channel genes, investigators examined whether variations in the genes were associated with type 2 diabetes risk in 7287 African-American and 3285 Hispanic-American postmenopausal women. Several variants stood out in the Journal of Nutrition study.