PILOT: The Effects of Short Term Administration of a Novel Glutathione Precursor (FT061452), on Serum and Intracellular Glutathione Levels
Glutathione (gamma-glutamyl-cysteine-glycine; GSH) is a powerful antioxidant found within
every cell. GSH is predominantly known to protect the cells from damage caused by free
radicals. The concentration of glutathione declines with age, stress, and in some
age-related diseases. When glutathione becomes deficient, a series of events are initiated
termed "oxidative stress" and the associated cell signaling leads to impaired immune
function and similar abnormalities in numerous cell systems.
Oral glutathione is ineffective in replenishing glutathione levels and reversing the
abnormal signaling pathways associated with oxidative stress. Intravenous glutathione has
been shown to be effective but is short-lived. N-Acetyl Cysteine, a glutathione precursor,
has had limited efficacy in clinical settings and suffers from an adverse effect
profile.Null Hypothesis (primary): The administration of FT061452 will not increase serum
and intracellular glutathione levels in comparison to N-Acetyl Cysteine (NAC), and placebo.
Null Hypothesis (secondary): The administration of FT061452 will not improve vascular
function in comparison to N-Acetyl Cysteine (NAC), and placebo.
The Specific Aims of this pilot study are to:
- Compare the change in serum and intracellular glutathione levels following the
administration of a novel oral glutathione precursor, FT061452, (modified glutathione
with selenium added, and cystine replacing cysteine, in doses equivalent to NAC)
compared to low dose or usual dose of NAC, and placebo.
- Compare the change in select clinical parameters (vascular function) following the
administration of a novel oral glutathione precursor, FT061452, (modified glutathione
with selenium added, and cystine replacing cysteine) compared to N-Acetyl Cysteine
(NAC), and placebo.
- As a pilot study a third goal is to generate effect sizes for appropriately powering
future clinical trials.
Background:
Increased rates of adverse health outcomes for racial and ethnic minorities have been linked
to a confluence of socio-cultural, environmental, immunological, and genetic based factors,
frequently acting in concert. Ultimately, the majority of these factors lead to adverse
physiologic and cellular changes. However, it is the chronic activation of these
neurohormonal systems through the above stresses that lead to maladaptive health
consequences such as accelerated apoptosis, atherogenesis, altered immune function, and
other dysregulations of cellular function. Ultimately, stress related cellular activities
contribute to many of the observed premature chronic diseases in humans, many of which are
found in disproportionately high rates in minority communities. Glutathione is the major
regulator of the cellular oxidative state that buffers many of these stress related
pathways. When glutathione becomes deficient there occurs an increase in reactive oxidative
species (ROS) that collectively can be termed "oxidative stress". Clinically, oral
glutathione (GSH) has been ineffective in replenishing glutathione levels and reversing the
associated abnormal cellular signaling. GSH as a whole molecule cannot be taken up by cells
in mammals but is largely metabolized in the gastrointestinal tract into constituent amino
acids, including the highly oxidizable L-cysteine, which cannot be re-united extracellularly
into glutathione as its re-assimilation requires two cytosolic, ATP-dependent enzymes. Thus,
the processes that achieve glutathione synthesis require special conditions that are only
present within the cell. Oral glutathione preparations are limited by their ability to
provide adequate substrate to stimulate intracellular glutathione synthesis due to
L-cysteine being highly oxidizable. Intravenous glutathione administration is expensive,
short-lived, and impractical, as the transiently higher plasma concentrations are largely
independent of intracellular glutathione activity, where much of the oxidative balance is
performed. N-Acetyl Cysteine (NAC), a glutathione precursor, has had limited efficacy in
clinical settings and suffers from an adverse side-effect profile. However, preliminary
findings of a novel glutathione precursor with vitamin implications (FT061452) indicate it
can affect the metabolism of glutathione via 2 mechanisms: 1) increasing the availability of
intracellular cysteine by using the more stable cystine as the physiologic and more stable
cysteine carrier which can traverse the cell membrane and create a more optimal Cys/CySS
redox state, and 2) adding selenium, an important co-factor for glutathione reductase. Thus,
FT061452 appears to provide a greater cellular delivery of substrate to attenuate oxidative
stress, in comparison to traditional glutathione precursors, which despite showing
promise,have not demonstrated consistent clinical efficacy.
Preliminary studies ; Preliminary studies to investigate GSH and several GSH analogs might
protect spermine-induced apoptosis in aortic vascular smooth muscle cells (VSMC) have been
promising. Given that spermine (a uremic toxin) increases intracellular ROS and promotes
apoptosis in some cultured cells, we first examined the generation of ROS along with
intracellular levels of reduced GSH and the ratio of reduced GSH and oxidized glutathione
(GSH/GSSG) in VSMC in response to spermine treatment and its attenuation by concomitant
administration of similar strengths of GSH, NAC and FT061452. While concomitant exposure of
these cells to NAC, GSH, or FT061452 attenuated spermine-induced decrease in GSH levels,
only the addition of the novel glutathione precursor, FT061452, to spermine treated cells
increased intracellular GSH levels above control values.
Study Design & Method:
This is a prospective randomized controlled pilot study, which will include twenty-four (24)
healthy individuals between ages of 40-75 years old. The study will occur over the course of
two days. On Day 1, potential subjects will be screened to determine eligibility by mini
history and physical exam, complete blood count (CBC) and complete metabolic panel (CMP). On
Day 2, eligible subjects will report to Participant and Clinical Interactions Resource
Center (formerly known as the CRC) after fasting overnight. The first 12 subjects (low dose)
will be randomized into three groups, 1) those given a single dose of placebo, 2) those
given 600 mg (low dose) of N-Acetyl Cysteine (NAC) or 3) those given 3000 mg of study drug
(FT061452). Serum and intracellular glutathione levels, biomarkers, and non-invasive
measures of vascular function will be assessed at baseline, 2, 4 and 6 hours. During their
stay in CRC, subjects in every group will be fed the same meal. The second 12 subjects
(usual dose) will be randomized into three groups, 1) those given a single dose of placebo,
2) those given 1200 mg (usual dose) of N-Acetyl Cysteine (NAC) or 3) those given 6000 mg of
study drug (FT061452). Serum and intracellular glutathione levels, biomarkers, and
non-invasive measures of vascular function will be assessed at baseline, 2, 4 and 6 hours.
During their stay in CRC, subjects in every group will be fed the same meal.
At baseline, 2, 4 and 6 hours, a blood sample (15 cc per draw) will be obtained for serum
and intracellular glutathione levels, stored serum for biomarkers, and non-invasive measures
of vascular function will be assessed at baseline and 6 hours, as follows: 1) Pulse wave
velocity and Augmentation Index (via SphygmoCor): (central artery pressure and central
aortic pulse pressure) and 2) Peripheral vascular endothelial function (via EndoPat): (%
flow mediated dilation).
This study has potential benefits to others. The knowledge gained will provide realistic and
practical information that guides the implementation of a non-pharmacological intervention
to reduce the progression of age related morbidities. Because CDU's community is largely
minority, the community of color will be included in this recruitment. The IRB exercises
oversight of all protocols involving human subjects, monitors for adverse events, and
performs audits of all approved protocols.
Interventional
Allocation: Randomized, Endpoint Classification: Pharmacokinetics/Dynamics Study, Intervention Model: Parallel Assignment, Masking: Open Label, Primary Purpose: Prevention
The change in serum and intracellular glutathione levels following the administration of a novel oral glutathione precursor
The change in serum/intracellular glutathione levels following the administration of a novel oral glutathione precursor, FT061452, (modified glutathione with selenium added, and cystine replacing cysteine) compared to N-Acetyl Cysteine (NAC), and placebo.
one day
No
Naureen Tareen, MD
Principal Investigator
Charles Drew University
United States: Institutional Review Board
10 - 04 - 2268 - 01
NCT01251315
December 2010
June 2011
Name | Location |
---|---|
Charles Drew University | Los Angeles, California 90059 |