Health & Medicine

Dysfunctional stem cells cited as cause for pulmonary fibrosis

Retinal pigment epithelium precursor cells Human embryonic stem cells differentiating into precursors cells of the retina. Nuclei are in blue. Pink indicates the presence of Pax6, a protein found in retinal tissue. The retinal pigment epithelium is the tissue responsible for macular degeneration, the most common cause of blindness.
Retinal pigment epithelium precursor cells Human embryonic stem cells differentiating into precursors cells of the retina. Nuclei are in blue. Pink indicates the presence of Pax6, a protein found in retinal tissue. The retinal pigment epithelium is the tissue responsible for macular degeneration, the most common cause of blindness. University of California, Santa Barbara

Pulmonary fibrosis is a mystifying, deadly lung disease that typically kills patients three to five years after diagnosis.

In most cases, there’s no cure and no known cause. Now, a recent study by Cedars-Sinai Medical Center in Los Angeles has identified one major culprit: dysfunctional stem cells.

Specifically, the problem occurs in special stem cells known as AEC2s that repair and regenerate lung cells damaged by viral infections, pollution or other injuries. In patients with fibrosis, those stem cells don’t do their job.

“Pulmonary fibrosis slowly robs patients of breath and finally life,” said Dr. Paul W. Noble, chairman of Cedars-Sinai’s Department of Medicine, in a statement. “In our study, we identified novel potential pathways to finding treatments for this relentless disease.”

Noble said one approach would be to test drugs that stimulate the development of AEC2 stem cells in patients whose lungs don’t have enough of them. “We can use these cells to create tiny ‘lungs in a dish’ as tools for drug development,” he said.

The study, published in Nature Medicine Journal, was funded by the California Institute for Regenerative Medicine and the National Institutes of Health.

Older moms more likely to live to 90

Women who have first babies later in life – deemed 25 or older – are more likely to live to age 90, according to a new University of California, San Diego, School of Medicine study.

It found that 54 percent of older, first-time mothers reached the age of 90, based on long-term data from 20,000 women collected nationwide as part of the national Women’s Health Initiative study. Those women were also more likely to be married, have college degrees and earn higher incomes and were less likely to be obese or have a history of chronic disease.

In recent decades, the average age of first-time motherhood in the U.S. has been rising, reaching 26.3 years in 2014, partly due to a decrease in teen mothers and an uptick of mothers over 30. Between 2000 and 2014, the number of women under 20 having a first child dropped 42 percent, while first births at age 35 and older jumped 23 percent, according to the National Center for Health Statistics.

The study does not recommend that women delay having a child, mainly because the risk of “obstetric complications,” such as gestational diabetes and hypertension, is greater with older mothers.

The study said there could be many factors affecting why waiting later to have a child increases longevity.

“It is possible that surviving a pregnancy at an older age may be an indicator of good overall health and, as a result, a higher likelihood of longevity,” said Aladdin Shadyab, a research scholar with UC San Diego’s Department of Family Medicine and Public Health. He said it’s also possible that older women “were of a higher social and economic status,” which improved their odds of living longer.

He said more study is needed to determine which socioeconomic factors might best explain the relationship between a woman’s first-birth age and living longer.

Black, Hispanic babies fare worse on breast-feeding

Further underscoring the health benefits of longer breast-feeding, a UC Davis researcher and others found that babies who were breast-fed less than six months had higher death rates and more ear infections and gastrointestinal disease. The disparities were higher among black and Hispanic babies, compared with white infants.

Calling it the first study to show how breast-feeding differences translate into health outcomes, the researchers used computer modeling to compare how “suboptimal” breast-feeding – less than six months – negatively affects black and Hispanic infants, compared with white babies.

For instance, the study found that ear infections were 1.7 times more common in black babies and 1.4 times as common in Hispanics than white babies; gastrointestinal infections were about 1.3 times more common among both black and Hispanic infants.

Differences in death rates were even more pronounced among infants breast-fed less than six months: 2.2 times the number of black infants and 1.5 times the number of Hispanic infants, compared with white babies.

“These lives matter,” said study co-author Eleanor Bimla Schwarz, professor of general medicine at UC Davis Health System, in a statement. “Breast-feeding mothers need our full support as a community, both in initiating and sustaining breast-feeding.”

New mothers are encouraged to feed their babies exclusively breast milk for the first six months, then complement breast milk with foods for the first year. According to the study, white mothers tend to breast-feed longer and have higher rates of exclusive breast-feeding.

The study, co-authored by six researchers at universities nationwide, also found that a shorter duration of breast-feeding impacts a mother’s health, with black and Hispanic mothers having a higher incidence of diabetes and hypertension. It also noted that infants’ ear infections and gastrointestinal issues can cause financial hardships for mothers who must take time off work to care for their babies.

Claudia Buck: 916-321-1968, @Claudia_Buck

  Comments