Poodle Update - Summer 2022 - 5

POODLE Update
antibiotic therapies by Dr. Haystead
and his laboratory. The North Carolina
State researchers are testing the
therapies, and those that appear
promising are sent to Dr. Embers
and her group to review their effectiveness.
" The goal is to get down
to the heart of the Bartonella DNA
and pick up molecular candidates
that can be worked into effective
therapies, " Dr. Breitschwerdt says.
Dr. Breitschwerdt is quick to give
credit to advances made from his
five-year study of the prevalence of
bartonellosis in dogs with splenic and
cardiac HSA funded by the AKC
Canine Health Foundation through
its Hemangiosarcoma Research Initiative.
Since 1995, the Foundation
and its donors have invested over
$4.8 million in 33 grants to understand
the mechanisms and causes,
new targets for treatment and early
diagnostics for HSA. Versatility in
Poodles, a worldwide community of
enthusiasts helping to advance breed
health and promote breed versatility,
is helping to sponsor this research
that goes through January 2023.
An early report of this research was
published in PLOS ONE in January
2020. Using polymerase chain reaction
(PCR) testing, the research team
studied fresh frozen HSA tissue,
fresh frozen non-tumor tissue, and
whole blood and serum from 110
dogs representing 39 breeds and
mixed breeds looking for Bartonella,
Babesia parasites and Hemotropic
Mycoplasma bacteria.
" While 73 percent of all tissue
samples from these dogs were
positive for Bartonella DNA, none
of the blood samples were, which
indicates that whole blood samples
do not reflect this pathogen, " Dr.
Breitschwerdt says. " The presence
of Bartonella DNA in 57 percent of
cardiac HSA tumors and in 93 percent
of non-tumor cardiac tissue is
an important finding. "
Knowing that Bartonella species,
B. hensalae specifically, is wellestablished
as a promoter of tumor-cell
proliferation and chronic
inflammation, the team speculated
that B. hensalae is a likely cofactor
in the development of HSA in dogs.
" Because dogs with HSA have
increased amounts of plasma
vascular endothelial growth factor
(VEGF) compared to healthy dogs
and because VEGF is present in
tumors, this implicates B. hensalae
as a possible cause of HSA, " Dr.
Breitschwerdt explains.
" In laboratory cultures, we have seen
how B. hensalae induces angiogenesis,
the formation of new blood vessels
from existing blood vessels, and
proliferation of endothelial cells by
stimulating the production of VEGF. "
CHALLENGES DIAGNOSING
BARTONELLOSIS
More than 44 Bartonella species
and subspecies are recognized today,
about half of which are associated
with disease symptoms. Although
the Bartonella pathogen has existed
5
" The presence of Bartonella
DNA in 57 percent of
cardiac HSA tumors and
in 93 percent of nontumor
cardiac tissue is
an important finding. "
Edward B. Breitschwerdt, DVM, DACVIM,
the Melanie S.. Steele Distinguished
Professor of Medicine and Infectious
Diseases and co-director of the Vector
Borne Disease Diagnostic Laboratory
at North Carolina State University

https://www.akcchf.org/research/research-portfolio/2519.html https://www.akcchf.org/research/research-portfolio/2519.html https://www.akcchf.org/research/research-portfolio/2519.html https://www.akcchf.org/canine-health/top-health-concerns/canine-cancer/hemangiosarcoma/hemangiosarcoma-initiative.html https://www.akcchf.org/canine-health/top-health-concerns/canine-cancer/hemangiosarcoma/hemangiosarcoma-initiative.html https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0227234 https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0227234

Poodle Update - Summer 2022

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