Vitamin D deficiency leads to obesity, stunted growth in zebrafish

September 29, 2020

Using a zebrafish model, researchers from North Carolina State University have found that vitamin D deficiency during early development can disrupt the metabolic balance between growth and fat accumulation. The results suggest a linkage between vitamin D and metabolic homeostasis, or equilibrium.

The research team, led by Seth Kullman, professor of biological sciences at NC State, looked at groups of post-juvenile zebrafish on one of three diets: no vitamin D (or vitamin D null), vitamin D enriched and control. The zebrafish spent four months on their particular diet, then the researchers looked at their growth, bone density, triglyceride, lipid, cholesterol and vitamin D levels. They also examined key metabolic pathways associated with fat production, storage and mobilization and growth promotion.

The zebrafish in the vitamin D deficient group were, on average, 50% smaller than those in the other two groups, and they had significantly more fat reserves.

"The vitamin D deficient zebrafish exhibited both hypertrophy and hyperplasia - an increase in both the size and number of fat cells," Kullman says. "They also had higher triglycerides and cholesterol, which are hallmarks of metabolic imbalance that can lead to cardio-metabolic disease. This, combined with the stunted growth, indicates that vitamin D plays an important role in the ability to channel energy into growth versus into fat storage."

After the initial testing, the vitamin D deficient zebrafish were given a vitamin D enriched diet for an additional six months, to see if the results could be reversed. While the fish did continue to grow and begin to utilize fat reserves, they never caught up in size with the other cohorts and they retained residual fat deposits.

"This work shows that vitamin D deficiency can influence metabolic health by disrupting the normal balance between growth and fat accumulation," Kullman says. "Somehow the energy that should be going toward growth is getting shunted into creating fat and lipids, and this occurrence cannot be easily reversed. While we don't yet understand the mechanism, we are beginning to tease that out."

Future work will involve looking at the offspring of vitamin D deficient mothers, to determine whether this vitamin deficiency has epigenetic effects that can be passed down.
-end-
The research appears in Scientific Reports and is supported by the Environmental Protection Agency (STAR RD-83342002) and the National Institute of Environmental Health Sciences (grants T32 ES07046, P30ES025128, R35ES030443 and P42ES004699). Kullman is corresponding author. Megan Knuth, former NC State Ph.D. student currently at the University of North Carolina Chapel Hill, is first author. Debin Wan and Bruce Hammock, both from the University of California Davis, also contributed to the work.

Note to editors: An abstract follows.

"Vitamin D deficiency serves as a precursor to stunted growth and central adiposity in zebrafish"

DOI: 10.1038/s41598-020-72622-2

Authors: Megan M. Knuth, Debabrata Mahapatra, Dereje Jima, Mac Law, Seth W. Kullman, North Carolina State University; Debin Wan, Bruce Hammock, University of California Davis

Published: Online Sept. 29, 2020 in Scientific Reports

Abstract:

Emerging evidence demonstrates the importance of sufficient vitamin D (1α, 25-dihydroxyvitamin D3) levels during early life stage development with deficiencies associated with long-term effects into adulthood. While vitamin D has traditionally been associated with mineral ion homeostasis, accumulating evidence suggests non-calcemic roles for vitamin D including metabolic homeostasis. In this study, we examined the hypothesis that vitamin D deficiency (VDD) during early life stage development precedes metabolic disruption. Three dietary cohorts of zebrafish were placed on engineered diets including a standard laboratory control diet, a vitamin D null diet, and a vitamin D enriched diet. Zebrafish grown on a vitamin D null diet between 2-12 months post fertilization (mpf) exhibited diminished somatic growth and enhanced central adiposity associated with accumulation and enlargement of visceral and subcutaneous adipose depots indicative of both adipocyte hypertrophy and hyperplasia. VDD zebrafish exhibited elevated hepatic triglycerides, attenuated plasma free fatty acids and attenuated lipoprotein lipase activity consistent with hallmarks of dyslipidemia. VDD induced dysregulation of gene networks associated with growth hormone and insulin signaling, including induction of suppressor of cytokine signaling. These findings indicate that early developmental VDD impacts metabolic health by disrupting the balance between somatic growth and adipose accumulation.

North Carolina State University

Related Cholesterol Articles from Brightsurf:

Cholesterol's effects on cellular membranes
The findings have far-reaching implications in the general understanding of disease, the design of drug delivery methods, and many other biological applications that require specific assumptions about the role of cholesterol in cell membranes.

Autism-cholesterol link
Study identifies genetic link between cholesterol alterations and autism.

Microbes might manage your cholesterol
Researchers discover a link between human blood cholesterol levels and a gene in the microbiome that could one day help people manage their cholesterol through diet, probiotics, or entirely new types of treatment.

Experimental cholesterol-lowering drug effective at lowering bad cholesterol, study shows
Twice-yearly injections of an experimental cholesterol-lowering drug, inclisiran, were effective at reducing low-density lipoprotein (LDL) cholesterol, often called bad cholesterol, in patients already taking the maximum dose of statin drugs, according to data of the ORION-10 trial presented Saturday, Nov.

Rethinking how cholesterol is integrated into cells
Cholesterol is best known in connection with cardiovascular disease, but cholesterol is also vital for many fundamental processes in the body.

Seed oils are best for LDL cholesterol
Using a statistical technique called network meta-analysis, researchers have combined the results of dozens of studies of dietary oils to identify those with the best effect on patients' LDL cholesterol and other blood lipids.

Cholesterol leash: Key tethering protein found to transport cellular cholesterol
Cholesterol is an essential component of living organisms, but the mechanisms that transport cholesterol inside the cell are poorly understood.

New way to treat cholesterol may be on the horizon
A breakthrough discovery by scientists at Houston Methodist Research Institute could change the way we treat cholesterol.

How low should LDL cholesterol go?
New analysis shows that in a high-risk population, achieving ultra-low LDL cholesterol levels, down to <10 mg/dL, safely results in additional lowering of risk of cardiovascular events.

Does boosting 'good' cholesterol really improve your health?
A new review addresses the mysteries behind 'good' HDL cholesterol and why boosting its levels does not necessarily provide protection from cardiovascular risk for patients.

Read More: Cholesterol News and Cholesterol 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.