A Non-Viral Gene Therapy Restores Mouse Hearts

Published on: September 3, 2025

A recent study investigated the roles of 12,13-diHOME in cardiac function restoration. The researchers examined the molecular mechanisms behind the effects of this specific molecule on the hearts of aged mice [1].

The Aging Heart

Aging significantly impacts the cardiovascular system, leading to alterations that are linked to disruptions in Ca²⁺ metabolism [2]. Concurrently, brown adipose tissue (BAT), which plays a protective role against metabolic and cardiovascular diseases, also diminishes with age [3].

Previous research from this group established a connection between BAT and enhanced calcium signaling as well as improved cardiac function in younger, healthy mice. The molecule 12,13-diHOME, a lipid-controlling hormone recognized as a lipokine, was found to be a critical mediator in these processes [4]. This study aims to explore the relationship between aging, BAT, and the decline in cardiovascular health.

Transplanting Fat

The documented decline in BAT’s thermogenic function with age is notable [3]. However, its endocrine function remains less understood. The researchers measured circulating lipids in plasma samples from:

• Human participants aged 65-90
• Young individuals aged 18-35
• Aged and young male mice

Age clearly affected lipid signaling among both humans and mice, showing overlap in the reduced levels of seven oxylipins, including 12,13-diHOME, in aged specimens compared to their younger counterparts. The transplantation of BAT from young mice into the visceral cavities of matched aged mice resulted in significant improvements in several metrics regarding cardiac function, suggesting that BAT transplantation was beneficial in mitigating age-associated cardiac issues.

A Non-Viral Gene Therapy Approach

Investigating the practical application of fat transplantation in clinical settings, researchers tested whether acute treatment with 12,13-diHOME could yield comparable results. It was found that this treatment improved cardiac functions in male aged mice but did not show the same effectiveness in female mice.

Recognizing that 12,13-diHOME has a short half-life of merely 30 minutes post-injection, the research team then employed a non-viral gene therapy approach: tissue nanotransfection (TNT). This innovative method facilitated the introduction of genes responsible for 12,13-diHOME production via a strand of circular DNA, delivered into mouse skin cells through a brief electric pulse over six weeks. This resulted in sustained overexpression of 12,13-diHOME, thereby enhancing circulation of the molecule and facilitating notable improvements in cardiovascular health for both male and female aged mice.

“In just six weeks, we were able to really negate a lot of the effects of cardiovascular aging by using TNT to increase 12,13-diHOME. The results were quite striking with improvements to ejection fraction and the heart’s pumping cycles.” – Daniel Gallego-Perez, Ph.D., Professor of Biomedical Engineering at The Ohio State University

Male-Specific Mechanism

To explore the observed molecular changes, the researchers analyzed gene expression in heart tissues of:

1. Young mice
2. BAT-transplanted aged mice
3. Aged control group (all male)

Gene expression analysis indicated elevated ER stress markers in the aged control group, while those undergoing BAT transplantation exhibited levels akin to younger counterparts. Similarly, male mice receiving gene therapy showed improvements.

Unexpectedly, there were no shifts in ER stress levels among female mice, potentially attributable to lower baseline ER stress in this group.

Additional investigations involved mice lacking neuronal nitric oxide synthase (nNOS), required for the beneficial effects of 12,13-diHOME on cardiac function [4]. The study highlighted that both ER stress and cardiac function failed to show improvement in nNOS-deficient mice after 12,13-diHOME treatment, indicating the molecule’s mediating role in cardiac health.

The findings further illuminated the significant role of Ca²⁺/calmodulin-dependent protein kinase II (CaMKII). Known for mediating ER stress and linked to cardiac dysfunction, this kinase is known to increase with aging [5] [6].

Overcoming Limitations

Kristin Stanford, Ph.D., the study leader, stated, “One of the biggest things we see with aging is cardiovascular disease, which increases dramatically in patients over 65. Now we’re correlating it to a decrease in the lipokine 12,13-diHOME, and we’re showing directly that increasing this lipokine can essentially rescue cardiac function.”

The results of this study corroborate prior data demonstrating significantly lower levels of circulating 12,13-diHOME in patients with cardiovascular disease when compared to healthy age-matched individuals [4]. However, the therapeutic applications of 12,13-diHOME were largely overlooked due to its short half-life. This research bridges that gap through the usage of innovative gene therapy techniques.

It should be noted that while notable improvements were documented in both male and female aged mice, the mechanism of action behind 12,13-diHOME was identified as being sex-specific; thus, further research is warranted to understand its workings within female models. Additionally, human trials are still necessary to validate these findings.

Literature

• Nirengi, S., et al. (2025). 12,13-diHOME protects against the age-related decline in cardiovascular function via attenuation of CaMKII. Nature Communications, 16(1), 7088.
• Janczewski, A. M., & Lakatta, E. G. (2010). Modulation of sarcoplasmic reticulum Ca(2+) cycling in systolic and diastolic heart failure associated with aging. Heart Failure Reviews, 15(5), 431–445.
• Becher, T., et al. (2021). Brown adipose tissue is associated with cardiometabolic health. Nature Medicine, 27(1), 58–65.
• Pinckard, K. M., et al. (2021). A Novel Endocrine Role for the BAT-Released Lipokine 12,13-diHOME to Mediate Cardiac Function. Circulation, 143(2), 145–159.
• Timmins, J. M., et al. (2009). Calcium/calmodulin-dependent protein kinase II links ER stress with Fas and mitochondrial apoptosis pathways. The Journal of Clinical Investigation, 119(10), 2925–2941.
• McCluskey, C., et al. (2019). Compromised cardiovascular function in aged rats corresponds with increased expression and activity of calcium/calmodulin dependent protein kinase IIδ . Vascular Pharmacology, 118-119, 106560.