A diet high in prunes prevents bone loss associated with spinal cord injuries

October 06, 2020

Findings from a new study among mice show a diet high in dried plum (prunes) completely prevents bone loss associated with spinal cord injury (SCI), while also restoring some of the bone lost following SCI. These findings are a remarkable addition to a decades-long, growing body of evidence that indicates a positive connection between dried plums and bone health.

In addition to the new SCI study, previous clinical research has demonstrated a favorable bone response to prunes among post-menopausal women, along with animal-based research that shows a similar positive response among those exposed to radiation - such as astronauts in space.

"We are seeing an exciting 'dried plum effect' on bones," said Bernard Halloran, Ph.D., Professor Emeritus, University of California - San Francisco (UCSF). "In a variety of unique research scenarios, dried plum is consistently associated with a favorable bone response. No other compound appears to have the same degree of positive impact."

The latest study, Dried Plum Mitigates Spinal Cord Injury-induced Bone Loss in Mice, was published in the July 2020 issue of the Journal of the Orthopaedic Research Society - Spine. The research was led by Halloran and Xuhui Liu, M.D., San Francisco Veterans Affairs Medical Center, Department of Veterans Affairs and the Department of Orthopedic Surgery, UCSF.

The researchers conducted two separate experiments. In a prevention experiment, they looked at dietary supplementation with dried plum for mitigating the loss of bone induced by SCI. Then, in a recovery experiment, they examined if a dried plum diet could restore bone lost after SCI.

"This evaluation is particularly important as individuals who suffer SCI experience extremely rapid bone loss," said Liu. "The SCI-related bone loss then leads to an increased risk of fractures, osteoporosis, and overall morbidity and mortality."

Experiment #1: Dried Plum Prevents SCI-related Bone Loss

Liu explains that in the prevention evaluation, mice underwent SCI and were fed a diet containing 25% dried plum by weight or a control diet for up to four weeks. In vivo microCT scanning was performed three times, including at base line (immediately before SCI) and two and four weeks after SCI.

According to the findings, the dried plum diet completely prevented bone loss compared to control diets. In contrast, the control group diet resulted in 53% and 71% loss of bone volume at two and four weeks post injury, respectively.

Experiment #2: Dried Plum Restores Some SCI-related Bone Loss

In the recovery experiment, mice were divided into groups and fed a control diet for two or four weeks. Another group was fed a control diet for two weeks to allow bone loss and then switched to the dried plum diet for an additional two weeks. The findings reveal that after only two weeks, the dried plum diet partially restored bone that had already been lost to the SCI. Bone strength was also greater in the mice switched to the dried plum diet when compared to the mice fed the control diet for four weeks.

"There are two types of cells involved with bone metabolism - osteoblasts and osteoclasts. Osteoblasts help to build new bone, while osteoclasts are essentially 'bone eaters,'" and function to tear down bone," said Liu. "At this time, we believe that dried plum functions to inhibit the bone-eating osteoclasts and this results in more bone."

Following the animal study, a pilot clinical trial providing SCI patients with dried plum did not show bone response among those experiencing SCI years prior to the trial. However, investigators indicate that additional research is needed among patients immediately following SCI to determine if dried plum can mitigate the loss of bone and bone strength as it did in the newly injured mice.

Dried Plum Polyphenols Potentially Key in Positive Bone Response

According to Halloran and Liu, it remains unclear what bioactive compounds in dried plum are responsible for the beneficial effects on bone. However, the researchers suggest that the polyphenol content in dried plums may play a role.

Non-polyphenolic compounds in dried plum may also be involved, such as vitamin K and manganese. Both nutrients are recognized as contributing to the maintenance of normal bone. Future work will focus on identifying and isolating the bioactive factors in dried plums.

"In summary, dietary supplementation with dried plum or products derived from dried plum may prove to help slow the loss of bone induced by SCI, as well as to improve other bone-related conditions," said Halloran. "The consistency of bone response to dried plum is remarkable, especially considering that dried plums are a whole food approach to healthy eating, as well as being readily available, economical, safe and - by all indications - effective in supporting healthy bones."
-end-
The animal protocol for the study was in accordance with the NIH Guide for the Care and Use of Laboratory Animals and approved by the Animal Care and Use Committee at the Veterans Affairs Medical Center, San Francisco. The study was supported by a pilot research grant from the UCSF Core Center for Musculoskeletal Biology and Medicine (NIH1P30AR066262-01) and a research grant from the California Prune Board.

Reference:
Liu X, Liu M, Turner R, Iwaniec U, Kim H, Halloran B (2020) Dried plum mitigates spinal cord injury-induced bone loss in mice. JOR Spine. e1113. https://doi.org/10.1002/jsp2.1113

ABOUT THE CALIFORNIA PRUNE BOARD

Created in 1952, The California Prune Board aims to amplify the premium positioning and top-of-mind awareness of California Prunes through advertising, public relations, promotion, nutrition research, crop management and sustainability research, and issues management. The California Prune Board represents approximately 800 prune growers and 28 prune, juice, and ingredient handlers under the authority of the California Secretary of Food and Agriculture.

California Prune Board

Related Spinal Cord Injury Articles from Brightsurf:

Stem cells can help repair spinal cord after injury
Spinal cord injury often leads to permanent functional impairment. In a new study published in the journal Science researchers at Karolinska Institutet in Sweden show that it is possible to stimulate stem cells in the mouse spinal cord to form large amounts of new oligodendrocytes, cells that are essential to the ability of neurons to transmit signals, and thus to help repair the spinal cord after injury.

Spinal cord injury increases risk for mental health disorders
A new study finds adults with traumatic spinal cord injury are at an increased risk of developing mental health disorders and secondary chronic diseases compared to adults without the condition.

Co-delivery of IL-10 and NT-3 to enhance spinal cord injury repair
Spinal cord injury (SCI) creates a complex microenvironment that is not conducive to repair; growth factors are in short supply, whereas factors that inhibit regeneration are plentiful.

IU scientists study link between energy levels, spinal cord injury
A team of researchers from Indiana University School of Medicine, in collaboration with the National Institute of Neurological Disorders and Stroke, have investigated how boosting energy levels within damaged nerve fibers or axons may represent a novel therapeutic direction for axonal regeneration and functional recovery.

UBCO professor simplifies exercise advice for spinal cord injury
Professor Kathleen Martin Ginis says a major barrier to physical activity for people with a spinal cord injury is a lack of knowledge or resources about the amount and type of activity needed to achieve health and fitness benefits.

Robotic trunk support assists those with spinal cord injury
A Columbia Engineering team has invented a robotic device -- the Trunk-Support Trainer (TruST) -- that can be used to assist and train people with spinal cord injuries (SCIs) to sit more stably by improving their trunk control, and thus gain an expanded active sitting workspace without falling over or using their hands to balance.

Does frailty affect outcomes after traumatic spinal cord injury?
A new study has shown that frailty is an important predictor of worse outcome after traumatic spinal cord injury in patients less than 75 years of age.

Sleep and sleepiness 'a huge problem' for people with spinal cord injury
A new study led by a University of Calgary researcher at the Cumming School of Medicine (CSM) finds that fatigue and sleep may need more attention in order to prevent issues like stroke after spinal cord injury.

From spinal cord injury to recovery
Spinal cord injury disconnects communication between the brain and the spinal cord, disrupting control over part of the body.

Transplanting adult spinal cord tissues: A new strategy of repair spinal cord injury
Spinal cord injury repair is one of the most challenging medical problems, and no effective therapeutic methods has been developed.

Read More: Spinal Cord Injury News and Spinal Cord Injury Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.