ArticlePDF Available

Slippery Elm, its Biochemistry, and use as a Complementary and Alternative Treatment for Laryngeal Irritation

Authors:

Abstract

Slippery elm is an herbal medicine derived from the inner bark of the slippery elm (Ulmus rubra - also known as Red Elm or Indian Elm) tree. It has been used to treat edema and inflammation as an alternative/complimentary form of medicine for many years. In the United States, slippery elm is marketed commercially to treat upper airway inflammatory conditions, and its reported benefits in treating these conditions are ubiquitous in anecdotal contexts. Individuals with voice disorders and other inflammatory conditions of the upper airway (e.g., laryngitis) are increasingly seeking information related to the use of herbal medications such as slippery elm, although most clinicians are unfamiliar with these medications and do not understand their biological actions and purported benefits. Furthermore, no scientific evidence is available to support the validity of slippery elm’s use in treating upper airway inflammatory conditions. The purpose of this manuscript is to review the biochemical composition, biological actions, and purported societal use of slippery elm as a complementary or alternative medicine specific to upper airway inflammatory conditions, present results from a pilot study investigating the soothing effects of slippery elm on the tissue of the upper airway, and present a framework for potential scientific investigation of slippery elm and related herbal medications.
JIB2012; 1(1):17-23 ISSN: 2146-8338
http://jib.scopemed.org 17
Journal of Investigational
Biochemistry
available at www.scopemed.org
Original Research
Slippery elm, its biochemistry, and use as a complementary
and alternative treatment for laryngeal irritation
Christopher R. Watts 1, Bernard Rousseau 2
1Department of Communication Sciences & DisordersTexas Christian UniversityFort Worth, TX
2Department of OtolaryngologyVanderbilt University Medical CenterNashville, TN
Received:March 19, 2012
Accepted:April 17, 2012
PublishedOnline:May 12, 2012
DOI:10.5455/jib.20120417052415
Corresponding Author:
Christopher R Watts,
Texas Christian University
c.watts@tcu.du
Key words:Alternative Medicine, Larynx,
Voice, Slippery Elm
Abstract
Slippery elm is an herbal medicine derived from the inner bark of the slippery elm
(Ulmusrubra - also known as Red Elm or Indian Elm) tree. It has been used to treat edema and
inflammation as an alternative/complimentary form of medicine for many years. In the United
States, slippery elm is marketed commercially to treat upper airway inflammatory conditions,
and its reported benefits in treating these conditions are ubiquitous in anecdotal contexts.
Individuals with voice disorders and other inflammatory conditions of the upper airway (e.g.,
laryngitis) are increasingly seeking information related to the use of herbal medications such
as slippery elm, although most clinicians are unfamiliar with these medications and do not
understand their biological actions and purported benefits. Furthermore, no scientific evidence
is available to support the validity of slippery elm’s use in treating upper airway inflammatory
conditions. The purpose of this manuscript is to review the biochemical composition,
biological actions, and purported societal use of slippery elm as a complementary or
alternative medicine specific to upper airway inflammatory conditions, present results from a
pilot study investigating the soothing effects of slippery elm on the tissue of the upper airway,
and present a framework for potential scientific investigation of slippery elm and related
herbal medications. © 2012 GESDAV
INTRODUCTION
For thousands of years, humans have utilized the medicinal
properties of vegetation, or herbal medicines, to treat
ailments. In this context, herbal medicines fall under
contemporary classifications as a type of complementary
(used along with conventional medical treatments) and/or
alternative (used in place of conventional medical treatments)
medicine [1]. Between 1990 and 1997, the use of these
treatments among United States residents significantly
increased to a level of approximately 629 million annual
visits to practitioners of alternative medicine, which exceeded
the number of annual visits of U.S. residents to primary care
physicians [2]. By 2002, this number had stabilized, with the
most common form of alternative medicine utilized being
herbal medicines by over 38 million U.S. Adults [3].
One herbal medicine which has historic relevance to the
treatment of laryngeal and pharyngeal (upper airway)
conditions is slippery elm. Slippery elm is a substance
produced from the ground and dried bark of the slippery elm
tree, Ulmusrubra. It is considered a dietary supplement by
the US Food and Drug Administration (FDA), and as such it
is not regulated. However, the FDA has recognized slippery
elm as a safe and effective oral demulcent. Historically,
slippery elm has been used to treat irritation and
inflammation in mucosa via application of a poultice,
tincture, or tea [4].
According to the Natural Medicines Comprehensive
Database, slippery elm is used for the treatment of coughs,
sore throat, colic, diarrhea, constipation, hemorrhoids,
irritable bowel syndrome (IBS), cystitis, urinary
inflammation, urinary tract infections, syphilis, herpes,
expelling tapeworms, protecting against stomach and
duodenal ulcers, for colitis, diverticulitis, GI inflammation,
and acidity [5]. It has been used to treat inflammatory
conditions of mucous membranes, including as a component
of recipes in traditional Oriental medicine and use as a
poultice by Native Americans. In traditional Oriental
medicine, elm bark has been used for edema, inflammation,
and cancer [6]. Today, it can be found commercially in
products marketed to treat throat irritation such as herbal teas
and lozenges, but also in concentrated pill and liquid forms.
Journal of Investigational Biochemistry. 2012; 1(1):17-23
18 http://jib.scopemed.org
Table 1.Examples of anecdotally reported uses for slippery elm, specific to upper airway conditions.
Upper Airway
Condition
Purported Action
Source Examples
Inflammation & Edema
Soothes inflammation, reduces
swelling, heals damaged tissue
Van Wyk, B., & Wink, M. (2004) [8]
Mucosal Irritation
Relives soreness and irritation
in mouth and throat tissues
Law, D. (1972) [9]
Singing Difficulty
Aid to singing voice by relieving
dry or sore throat
Peirce, A. (1999) [10]
Boon, H., & Smith, M. (2004) [12]
Laryngitis
Coats and soothes mucous
membranes
Skidmore-Roth, L. (2005) [13]
Acid Reflux
Aids in the management of
reflux symptoms
Vemulapalli, R. (2008) [14]
It is also used as a dietary supplement. It’s reported anecdotal
benefits are considerable and societal use ubiquitous,
suggesting that society perceives this substance as beneficial
for upper airway mucosal irritation and/or inflammatory
conditions, even though scientific evidence supporting this
belief is virtually non-existent. Table 1 illustrates some of the
reported uses for slippery elm specific to upper airway
complaints and conditions.
Products containing slippery elm are frequently championed
by professional and non-professional voice users as beneficial
for alleviating adverse throat sensations. Companies often
market their products specifically to these populations, with
well known examples including Thayer’s Slippery Elm
Throat Lozenges® and Throat Coat®. Clinical voice
specialists including otolaryngologists and speech-language
pathologists might occasionally be presented with patients
who use and purport the benefits of these types of products.
This is supported by a report in 1995 which indicated that
41% of a treatment seeking population at a major voice center
made inquiries regarding the use of alternative treatments [7].
Information regarding the use of herbal medications as
complimentary or alternative form of treatment is sparse in
the communication disorders literature. In addition, few if
any graduate programs offer courses which educate clinicians
on this topic. As such, most practicing clinicians will be
unfamiliar with a product such as slippery elm when its use is
reported or questioned by a patient.
While the popularity and use of slippery elm among
individuals who use alternative medicines is clear, there is no
objective, empirical research available that investigates the
effectiveness of this herb for reducing inflammation and/or
soothing epithelial tissue. However, it would benefit health
professionals to have at least an elementary understanding of
this substance’s chemical makeup, known biological actions,
and recommended uses in order to (1) be able to understand
why a patient might be utilizing it, and (2) to better counsel
patients who question its application for their throat/voice
condition. The purpose of this paper is to present this
information by reviewing the biochemical composition,
biological actions, and purported societal use of slippery elm
as a complementary or alternative medicine specific to upper
airway inflammatory conditions. In addition, results from a
pilot study investigating the perceived soothing effects of
slippery elm in a non-treatment seeking population are
reported, along with a framework for potential scientific
investigation of slippery elm and related herbal medications
used for the treatment of voice or laryngeal conditions will be
presented.
Chemical Composition and Biological Actions
The slippery elm tree is a member of the elm family, with a
geographic distribution ranging along the eastern and central
United States. Its name is derived from the viscous, slimy
liquid created when the inner bark is chewed, which was
common among Native Americans and early pioneers as a
relief to dehydration and hunger. The inner bark is the only
part of the tree known to be used for medicinal purposes, and
the remainder of the tree has no significant commercial value.
The inner bark is thin, tough, and flexible with a fibrous
texture. The hue of the natural bark is a reddish-yellow or
reddish-brown color, although when dried and in powder
form (as is commonly used in medicinal applications) the
color is grayish [9-15].
A number of early investigations have shed light on the
biochemistry of slippery elm. The most abundant, and
medicinally important, biochemical components of slippery
elm are mucilage and tannins. Mucilage, which forms the
bulk of chemical compounds in slippery elm, is composed of
carbohydrates which, when added to water, swell to form a
viscous, sticky substance [11]. Pharmacologically, viscous
gel-like substances increase the retention time of polymers
over mucosal surfaces and facilitates adhesion. This has the
effect of coating mucous membranes and helping to
ameliorate adverse sensations and the involuntary reflexes
(e.g., coughing, throat clearing) triggered in response.
Mucous membranes are lined with mucus, a product of
mucins and inorganic salts suspended in water. Mucins
comprise a family of glycosylated proteins made up of
oligosaccharide chains attached to a protein core. They
contain a dense sugar coating providing substantial
hygroscopic properties and increased resistance to enzymatic
protein degradation [11]. Mucosal saliva contains a high
molecular weight mucin capable of binding to the oral
mucosal surface, an important mechanism for providing
lubrication and maintenance of hydration [11]. The affinity
of saliva and salivary mucin also contributes to host defense.
The bioadhesive nature of mucilage provides favorable
properties for drug delivery when solute bioavailability is
diminished by absorption or increased mucociliary clearance.
The mucilage components of slippery elm are displayed in
table 2. Mucilage constituents include monosaccharides
(e.g.,hexose, pentose), methylpentose (a monosaccharide with
an added methyl group) and uronic acids [16-17]. These
compounds are structured as to prevent them from being
Journal of Investigational Biochemistry. 2012; 1(1):17-23
http://jib.scopemed.org 19
dissolved, thus preserving their ability to retain water. As a
result, powder preparations of slippery elm can be used as a
demulcent (forms a film, or coating, over tissue) by mixing
the preparation with water to form a thick gel, which can be
applied to mucous membranes of the mouth and throat. Thus,
indications of mucilage in medicine include palliative care
and reducing discomfort from tissue irritation via emollient
(soothing) and demulcent (coating) effects [18].
Table 2.Chemical composition of slippery elm.Information from
Kemper (1999) [7], Anderson (1933) [15], and Hough, Jones,
&Hirst (1950) [16].
Biochemical Component
Mucilage
Uronic acid (36%)
Pentose (6.5%)
Hexose
Methylpentose (rhamnose, galactose) (25%)
Other
Tannins
Oxalate acid
Flavanoids
Phytosterols
Salicyclic Acid
Capric Acid
Caprylic acid
Decanoic acid
Tannins are water soluble polyphenolic constituents capable
of binding and precipitating proteins by way of hydroxyl and
carboxyl moieties. Carboxyl groups contain a single carbon
atom attached to an oxygen atom by double covalent bond
and to a hydroxyl group by single covalent bond (e.g., -
COOH). The binding and precipitation properties of tannins
allow for them to bind with protein-rich structures of the skin
such as collagen. Tannins have also been proposed to interact
with the plasma glycoproteins fibronectin and fibrinogen
[19]. Tannin phytochemicals possess potent astringent
properties. In medicine, tannins have been used for the
treatment of inflamed superficial skin diseases, and as a
desiccant in the treatment of weeping skin inflammations
such as shingles and acute eczema [19]. The mechanism of
action is thought to be related to the cross-linking of
structural proteins [19]. The precipitation of proteins and
sealing of cell membranes reduces tissue exudate, allowing
for dessication of the affected area and expedited healing.
Contraction of the skin and wound closure is mechanistically
important to prevent pathogen invasion. Thus, tannins exert
antimicrobial properties via their ability to expedite tissue
contraction. The fully closed wound prevents bacteria and
other substances from entering the wound bed.
Tannins also display strong antioxidant activity and
protection against reactive oxygen species. Several cellular
processes, including lipid peroxidation, protein denaturation,
carbohydrate and nucleic acid formation can be influenced by
free radicals generated during oxidative stress. The
accumulation of reaction oxygen species during oxidative
stress can interrupt normal physiologic cellular processes.
Phenolic compounds such as tannins are capable of inhibiting
these processes [20]. For example, the phytochemical
constituents of slippery elm have been shown to display
antiradical and radical scavenging properties by inhibiting the
formation of cytotoxic reactive species, such as peroxynitrite
(ONOO¯) [21].
Tannin phytochemicals are found naturally in many foods,
including wine, tea, and fruits, and are responsible for the
taste of bitterness in these products. Witch hazel, derived
from the plant of the same name, is a familiar medicinal
product which contains many tannins, where it is used as an
astringent for inflammatory skin conditions such as acne and
eczema. Tannins comprise no more than 3% of the chemical
composition of slippery elm, though their presence certainly
could have a local effect on pharyngeal/laryngeal tissue if
applied topically, such as with teas or lozenges.
Extracts from elm bark have been investigated scientifically
with regards to the anti-inflammatory and anti-oxidant
properties of this substance. It has been demonstrated that
elm bark has systemic anti-inflammatory effects in the
stomach and intestines of a porcine animal model [22]. Elm
bark has also been shown to influence immune system
activity through increased production of cytokines in a
murine animal model [6]. The potential anti-inflammatory
properties of slippery elm have definite relevance to voice
and other upper airway inflammatory conditions. If it can be
demonstrated that slippery elm is effective in reducing
inflammation in the upper airway, these findings may have
significant clinical value related to management options of
these conditions.
METHODS OF DELIVERY AND DOSAGE
A review of the preferred delivery method and dosage level
suggested by various herbal medicine texts and sources of
information on the internet revealed a large degree of
heterogeneity in both areas. Delivery methods fall into three
categories: liquid preparations, lozenges and capsules. Liquid
preparation forms of delivery are made by the production of a
decoction (boiling the bark or bark derivative in water), tea
(dried, ground bark steeped in hot liquid), or liquid extract [9-
10, 12]. These may be swallowed directly and/or gargled.
Formula content, directions, and additions of other herbal
ingredients in these liquid preparations vary widely from
source to source. Lozenges containing slippery elm are
consumed similar to cough lozenges, with the herbal contents
of the lozenge mixing with saliva and then swallowed.
Slippery elm capsules are typically marketed towards the
treatment of digestive ailments. These are taken orally and
believed to soothe the lower gastrointestinal tract once the
outer capsule is dissolved [10]. Oral capsules are marketed
by some vendors as alleviating upper airway irritation,
although no scientific evidence exists, and many questions
remain, regarding the systemic effects of slippery elm in the
upper airway after oral ingestion in pill form.
Various anecdotal “recipes” for teas and decoctions exist,
available for viewing on the internet and in the numerous
volumes of herbal medicine textbooks [9-13]. Because
Journal of Investigational Biochemistry. 2012; 1(1):17-23
20 http://jib.scopemed.org
slippery elm is not a regulated substance, there are no official
guidelines or recommendations for its use, and no empirical
investigations for dosage effects on upper airway
inflammatory conditions have been published. The
University of Maryland publishes a Complementary and
Alternative Medicine Index online whose dosage
recommendations are consistent with many of the information
sources identified. These include: (1) as a decoction, one part
bark to eight parts water, (2) as a tea (infusion), 4 grams of
powder steeped in 2 cups of water, and (3) as a capsule,
200mg-500mg three times a day [11]. While these levels are
commonly identified as recommended amounts, a large
degree of heterogeneity exists in dosage recommendations
among vendors of slippery elm and sources of information for
its use [9-13]. A review of vendor sources marketing slippery
elm capsules on the internet found dose level ranges between
200mg-600mg per capsule, with varying recommendations
for the number of doses per day. There are no reported side
effects of slippery elm, and no known correlation exists
between dose amount and the presence of adverse events
from slippery elm ingestion. It has been reported that
slippery elm has abortive effects, and its use by females who
are pregnant is not recommended.
Pilot Study
Purpose: The purpose of the study was to determine if
slippery elm effects a change in laryngeal/pharyngeal
sensation of “soothing” compared to a control treatment when
measured at one, five, and ten minutes after receiving
treatment.
Design: Randomized control (single blind) treatment design
with alternative treatment as the control. The study was
approved by a university Institutional Review Board.
Participants: 24 graduate speech-language pathology students
(22 females, 2 males) were recruited via a convenience
sample and randomly allocated (based on order in which they
volunteered, 12 participants in each group) to the treatment or
control group. To be included in the study, it was required
that participants reported no current pharyngeal or laryngeal
complaints including irritation or soreness, upper respiratory
infection, or voice problems. Due to the report of potential
abortive effects of slippery elm, female participants were
asked if they were currently pregnant, think they may be
pregnant, or are planning to become pregnant, and if they
indicated “yes” to either of those questions they were
excluded from the study.
Procedures: Testing for each participant was completed in
one day. After consent procedures, participants were seated in
front of a desk, and served a warm 6oz beverage in an
unlabeled white Styrofoam cup, so that they were blind to
group. Participants were asked to consume the 6oz within 3
minutes. Participants received one of two possible warm
liquid stimuli (liquid was boiled in a commercial electric
kettle and allowed to sit for 45 seconds before pouring into
cup), depending on their group allocation. Participants
allocated to the experimental group received a tea consisting
of water mixed with 2 tsp (3g) of pure slippery elm powder
(Now Foods, Bloomingdale, IL). The slippery elm tea was
flavored with 2 drops of orange flavoring (Frontier Natural
Products Co-op, Norway, IA.). The orange flavoring
contained organic orange oil and organic sunflower oil, and
was used to flavor beverages in each group. Participants
randomly allocated to the control group received a warm tea
consisting of water steeped with Decaffeinated Lipton’s
orange pekoe tea (Unilever PLC, London, U.K.). This tea
was also flavored with 2 drops of the orange flavoring.
Once all the beverage was consumed (confirmed by the PI
looking into the cup), a timer was started. After 1, 5, and 10
minutes, each participant was asked to rate the degree to
which pharyngeal sensations changed from baseline (prior to
drinking beverage), if at all, in response to the following
sentence & question: Tissue is soothed when the surface
feels as if it were coated with something, such as a layer of
protective covering. To what degree does your throat feel
soothed compared to before you had a drink?
Participants responded to this prompt at each measurement
interval using a 5-point equal appearing interval (EAI) where
0 corresponded to no change from baseline (before
consuming beverage) and 4 corresponded to strong, very
noticeable change. A total of 3 measurements from each
participant were obtained (one measurement at each temporal
interval 1, 5, and 10 minutes).
Data Analysis: This study was comprised of two independent
variables: group (slippery elm vs. control) and time (one, five,
and ten minutes post consumption of beverage). As ordinal
data was used to measure perceptions of “soothing”, non-
parametric statistics were applied to the data, including
separate Friedman Anova’s applied to the time data
separately for each group and a Mann-Whitney U test
comparing the effect of slippery elm vs. control across the
three levels of time. Post-hoc testing, when appropriate,
utilized Wilcoxen sign-ranked tests, and a Bonferonni
correction (adjusting down from an initial value of 0.05) were
used when statistical tests involved more than one
comparison to protect against Type 1 error. All statistical
calculations were obtained using SPSS Statistics ver. 19
(IBM).
Results: Means and standard deviations of perceived
“soothing” ratings are reported in Table 3. At each
measurement time, the slippery elm group rated perceptions
of “soothing” greater than those of the control group. These
ratings were highest for both groups at the 1-minute interval
(slippery elm = 2.17; control = 1.75) compared to the later
time intervals, which appeared to decrease proportionally.
Table 3. Means and standard deviations (sd) of perceptual
ratings of “soothing” in groups receiving slippery elm and the
control tea in the three different levels of time.
Group
Time
Mean
SD
Slippery Elm
1-minute
2.17
1.12
5- minute
1.75
0.86
10-minute
1.42
1.24
Control
1-minute
1.75
1.22
5- minute
1.42
1.08
10-minute
1.17
1.19
To investigate an effect of measurement time on perceptions
of “soothing” separately for each group, Friedman Anova’s
were applied to the data. Results indicated a significant effect
of time in the measures of the slippery elm group (Fr =9.941;
Journal of Investigational Biochemistry. 2012; 1(1):17-23
http://jib.scopemed.org 21
p = 0.007) but not the control group (Fr = 7.280; p > 0.025)
when alpha level was adjusted to 0.025 using the Bonferonni
correction. Post-hoc tests on the three levels of time for the
slippery elm data utilized a Wilcoxon sign-rank test with
alpha level adjusted using the Bonferonni correction. Results
revealed a significant difference between ratings of soothing
measured at one and ten minutes (z = -2.714; p = 0.007), but
not the remaining two time comparisons.
Data from Table 3 were applied to statistical testing as a
function of group. To investigate the effect of slippery elm
vs. control on perceived “soothing” separate Mann-Whitney
U tests were applied to the group data at each measurement
time interval, with alpha level adjusted down appropriately
using the Bonferonni correction. Results revealed no
difference between perceived “soothing” at either the one
minute (U = 59.0; p > 0.017), five minute (U = 53.5; p >
0.017), or ten minute (U = 62.5; p > 0.017) measurement
intervals.
Discussion and Framework for Future Scientific
Investigation
The use of alternative and complimentary medicines in the
United States is widespread [2]. Treatment-seeking
populations with voice problems frequently request
information from clinicians regarding the use of these
substances, and also report their current use in managing
symptoms associated with upper airway complaints [7].
Nevertheless, clinical training programs typically do not
incorporate education in alternative medical treatments as
part of the curriculum, and the scientifically-validated
evidence for their use in upper airway conditions which affect
the pharynx and larynx is non-existent. It would benefit
clinicians to be aware of the different alternative and
complementary substances that might be used by a specific
treatment-seeking population (e.g., those with voice
disorders) and their scientifically validated effectiveness, as
speech-language pathologists are increasingly being asked for
information relative to their use in treating related conditions.
The results of the pilot study presented in this manuscript
revealed a significant influence of slippery elm on ratings of
laryngeal/pharyngeal “soothing” when measured at one
minute after treatment compared to ten minutes. There was
also a trend for ratings of “soothing” to be greater in
participants consuming slippery elm compared to those
consuming Lipton tea at each measurement interval, although
the difference did not reach the level of statistical
significance. A number of factors limited the power of the
current study, most notably sample size, which should be
addressed in future research focused on measuring clinical
outcomes of alternative medicine application in voice and
laryngeal conditions. Although the descriptive statistics
showed ratings of “soothing” in the slippery elm group being
greater at each measurement interval, it is likely that
statistical power was not large enough to detect a difference it
if actually existed. The definition we used to guide the
perceptual rating process may also have influenced outcomes
and should be addressed in future research. A
framework for building an evidence-based line of research to
acquire greater knowledge in this area is presented below.
Clinical outcome research is warranted with regards to the
effects of herbal alternative/complimentary medicines in the
treatment of voice disorders and upper airway inflammatory
conditions. An emphasis in clinical decision making based
on evidence-based information from clinical research has
been on the upsurge for decades, supporting the need for
studies that investigate the effectiveness of slippery elm and
other herbal medications in the treatment of laryngeal &
pharyngeal inflammatory conditions. These clinically-
oriented investigations should be planned with the strictest
possible scientific standards, as studies designed to eliminate
bias (as much as possible) are more likely to influence
clinical practice [23]. In addition to methodological rigor, it
is suggested that these investigations should follow a phased
process (e.g., initial small scale exploratory studies leading to
larger randomized controlled trials) designed to identify (1)
the activity induced by a treatment and (2) the subsequent
treatment effect and efficacy [23].
Phased clinical research is typically initiated as small scale
pre-clinical studies designed to assess treatment
activity/effect in laboratory models or exploratory studies
designed to measure activity/effect in a defined population.
This initial phase to clinical outcome research is the model
used by numerous private and public health-related
organizations, including the National Institutes of Health in
the U.S. As scientifically validated treatment activity and
effect are unknown for the use of slippery elm in treating
upper airway inflammatory conditions, it is recommended
that future programmatic research investigating this topic
begin as initial phase exploratory designs. Such designs
could include investigations of the cellular and molecular
activity induced by slippery elm in upper airway tissue (e.g.,
pharyngeal or laryngeal tissue) in animal models, and/or
identification of a possible soothing effect of slippery elm in
normal control populations.
Slippery elm is used as an emollient, demulcent, or anti-
inflammatory. The basic perceived effect of an emollient or
demulcent is to soothe irritated tissue, although with a
demulcent the perceived outcome is due to a surface coating
of protective mucilage while the perceived outcome of an
emollient is due to an increase in tissue surface hydration
(e.g., it moisturizes). The deposition of mucilage on the
surface of tissue and the hydration levels of tissue can be
measured via laboratory procedures. These measurements
can elucidate the chemical activity induced by treatment (e.g.,
changes within the tissue which occur at a cellular and
molecular level). However, to measure the treatment effect
(the degree of benefit to an individual) of an emollient or
demulcent, subjective measures must be utilized as any
changes in the degree of “soothing” induced by a treatment is
an obligatory perceptual experience which cannot be
measured with objective means. Thus, studies investigating
the soothing effect of slippery elm and/or other herbal
medications should include some perceptual scale or
measurement designed to assess this self-perceived
factor.Inflammation is a chemical reaction of tissue due to
some irritant or damage. Inflammatory responses can result
in perceptual experiences (e.g., pain in a sore throat), but the
process underlying inflammation occurs within the affected
tissue, due to changes in cellular and molecular activity. The
activity that is the inflammatory response can be objectively
measured, as can the change in this activity secondary to
some medical treatment. This means that the changes in
chemical activity that occur in an inflammatory process relate
Journal of Investigational Biochemistry. 2012; 1(1):17-23
22 http://jib.scopemed.org
directly to the effects of an anti-inflammatory medication
given to treat it. This differs from the relationship between
the activity induced by an emollient or demulcent and the
indirect perceptual experience of “soothing”. As such, anti-
inflammatory effects of medicines can be quantified
objectively, without relying on perceptual judgments. If the
purported effects of slippery elm are to soothe and reduce
inflammation, clinical research focusing on the effectiveness
of this herb should take into account the perceptual response
to its administration (in its capacity to soothe tissue) as well
as changes in the activity within tissue at the cellular and
molecular level (in its capacity to reduce inflammation), the
latter of which can be assessed via histochemical methods in
animal models.
SUMMARY
Herbal alternative/complimentary medications are being used
by and are of interest to populations with upper airway
inflammatory conditions which affect voice production and/or
adverse sensations in the throat. The anecdotally reported
benefits of slippery elm use in treating these conditions are
ubiquitous. However, no scientific evidence exists to support
these claims. There is evidence which supports anti-
inflammatory effects of elm bark in the lower digestive tract.
Research is needed to investigate the validity of slippery
elm’s use in managing upper airway inflammatory conditions.
Results from a small pilot study revealed trends of perceived
“soothing” being rated greater by those receiving slippery elm
compared to a control substance, although the effect did not
reach statistical significance. It is recommended that initial
exploratory pre-clinical or phase 1 trials be implemented to
study the perceptual soothing effects related to the emollient
and demulcent properties of slippery elm, and the cellular and
molecular activity related to the anti-inflammatory properties
of this herb. If the benefits of slippery elm are scientifically
validated, these findings could have a significant impact on
clinical decision making and management options.
ACKNOWLEDGMENTS
The authors would like to thank TerborFastalof of the Vox
organization for his inspiration and guidance for the authors
in developing the idea for this study and feedback on the
manuscript.
REFERENCES
1. What Is Complementary and Alternative Medicine? In:
National Center for Complementary and Alternative
Medicine Available via
http://nccam.nih.gov/health/whatiscam (Accessed 12
March 2012).
2. Eisenberg DM, Davis RB, Ettner SL, Appel S, Wilkey S,
Van Rompay M, Kessler R. Trends in alternative
medicine use in the United States.JAMA 1998; 280:
1569-75.
3. Tindle HA, Davis RB, Phillips RS, Eisenberg DM. Trends
in use of complementary and alternative medicine by US
adults. AlternTher Health Med 2005; 11: 42-49.
4. Kemper KJ. Slippery elm (Ulmusrubra or U. fulva). In:
The Longwood Herbal Task Center for Holistic Pediatric
Education and Research Force Available via
http://www.longwoodherbal.org/slipperyelm/slipperyelm.
pdf (Accessed 4 April 2012).
5. Jellin JM, Gregory P, Batz F, Hitchen K, Burson S, Shaver
K, Palacioz K (eds). Natural Medicines Comprehensive
Database. Therapeutic Research, Stockton, 2000.
6. Yousuk L, Hyunjin P, Ryu H, Chun M, Kang S, Kim HS.
Effects of elm bark (Ulmusdavidiana var. japonica)
extracts on the modulation of immunocompetence in
mice. Journal of Medicinal Food, 2007: 10:118-125.
7. D’Antoni ML, Harvey PL, Fried MP. Alternative
medicine: Does it play a role in the management of voice
disorders? J Voice 1995; 9: 308-311.
8. Van Wyk, B., &Wink, M. Medicinal Plants of the World.
Timber Press, Portland, Timber Press, pp. 329-430, 2004.
9. Law, D. The Concise Herbal Encyclopedia.St. Martin’s
Press, New York, pp. 220-238, 1972.
10. Peirce, A. The American Pharmaceutical Association:
Practical guide to natural medicines. Stonesong Press,
New York, pp/601-602, 1999.
11. University of Maryland. (2002). Slippery Elm.
Complementary and Alternative Medicine Index (CAM).
Retrieved October 5, 2007, from
http://www.umm.edu/altmed/articles/slippery-elm-
000274.htm
11. The Columbia Encyclopedia. 6th ed., Columbia
University Press, New York, 2005.
12. Boon, H., & Smith, M. The complete natural medicine
guide to the 50 most common medicinal herbs. Robert
Rose, Toronto, 2004.
13. Skidmore-Roth, L. Mosby's Handbook of Herbs &
Natural Supplements. 2nd ed., Mosby Elsevier, St. Louis,
2005.
14. Vemulapalli, R. Diet and lifestyle modifications in the
management of gastroesophageal reflux disease.
NutrClinPract 2008; 23: 293-298
15. Sudhakar Y, Kuotsu K, Bandyopadhyay AK.
Buccalbioadhesive drug delivery--a promising option for
orally less efficient drugs. J Control Release 2006; 114:
15-40.
16. Anderson E. The mucilage from slippery elm bark.J
BiolChem 1933; 104:163-170.
17. Hough L, Jones J, Hirst E. Chemical constitution of
slippery elm mucilage: Isolation of 3-methyl d-galactose
from the hyrodolysis products. Nature 1950; 165:34-35.
18. Boon H, Smith M. 50 Most Common Medicinal Herbs.
Robert Rose, Toronto, 2004.
19. Folster-Holst R, Latussek E. Synthetic tannins in
dermatology--a therapeutic option in a variety of pediatric
dermatoses. PediatrDermatol 2007; 24: 296-301.
20. Blokhina O, Virolainen E, Fagerstedt KV. Antioxidants,
Journal of Investigational Biochemistry. 2012; 1(1):17-23
http://jib.scopemed.org 23
oxidative damage and oxygen deprivation stress: a
review. Ann Bot (Lond) 2003; 91: 179-194.
21. Choi HR, Choi JS, Han YN, Bae SJ, Chung HY.
Peroxynitrite scavenging activity of herb extracts.
Phytother Res 2002; 16: 364-367.
22. Cho SK, Lee SG, Kim CJ. Anti-inflammatory and
analgesic activities of water extract of root bark
ofUlmusparvifolia. Kor J Pharmacognosy 1996; 27: 274
281.
23. Robey, R. & Schultz, M. A model for conducting clinical-
outcome research: an adaptation of the standard protocol
for use in aphasiology. Aphasiology 1998; 12: 787-810.
This article is an open access article licensed under the terms of the Creative Commons Attribution Non-Commercial License
(http://creativecommons.org/licenses/by-sa/3.0/) which permits unrestricted, non-commercial use, distribution and reproduction in any medium,
provided the work is properly cited.
... It is a member of the elm family that is most popular by the slippery elm (Ulmus rubra) which is a native tree in North America. According to Watts et al, the slippery elm bark is mainly composed of various fibers (that include insoluble cellulose, hemicellulose, lignin, and soluble mucilage) and tannins (Watts Rousseau, 2012). For UD elm barks, along with those, various bioactive components (e.g., lignin derivatives, catechin derivatives, flavonoids, phenolic compounds, etc.) have been reported (Jung et al., 2008;Lee et al., 2008). ...
... The main component responsible for the above medicinal usage is the mucilage that endows the UD bark powders unique physical properties of excellent swelling and gelling ability (Kang et al., 2020). The mucilage is large and highly branched polymers composed of different types of sugars and uronic acids coupled by glycosidic bonds (Watts et al., 2012). In our previous study, when the UD root bark powder was topically applied to the wound site in the animal model, it absorbed the exudates and swelled to form a viscous gel that could cover the wound and prevent further infection (Kang et al., 2020). ...
... This might be explained by the inhomogeneity of the UD gel film likely due to the immiscible compositions (e.g. water-insoluble fibers) of the UD root bark incorporated into the gel film (Watts et al., 2012). ...
Article
Full-text available
Ulmus davidiana var. japonica (UD) has widely been used in Korean traditional medicine for the treatment of various types of diseases including inflammation and skin wounds. The UD root bark powders possess gelling activity with an excellent capacity for absorbing water. This distinct property could make the UD root bark powders to be a great material for manufacturing a gel film specifically for the healing of large and highly exudating wounds (e.g., pressure sores and diabetic ulcers). In this research, we separated the UD root bark powder into 4 different samples based on their sizes and then tested their water absorption capacity and flowability. Based on these results, 75–150 μm sized and below 75 μm sized samples of UD root bark powders were chosen, and UD gel films were prepared. The UD gel films showed good thermal stability and mechanically improved properties compared with pullulan only gel film with excellent swelling capacity and favorable skin adhesiveness. Further, in the animal studies with the skin wound mice model, the UD gel films exhibited significant therapeutic effects on accelerating wound closure and dermal regeneration. Overall, this study demonstrated the applicability of UD root bark powders for hydrogel wound dressing materials, and the potential of UD gel films to be superior wound dressings to currently available ones.
... The mucilaginous inner bark of slippery elm (U. rubra) has been used as a remedy in North America for centuries. It is the only elm pharmaceutical that has survived modern scrutiny and is produced commercially to treat throat irritation (Watts and Rousseau 2012). Recent studies have shown that elm glycoproteins may have anti-cancer and anti-aging properties, and that flavonoid-C-glucoside compounds display osteoprotective effects (Jung et al. 2007;Hartmann et al. 2011;Sharan et al. 2011;Kim et al. 2012). ...
... The inner bark of U. rubra contains around 7 % mucilage, mainly composed of galactose, rhamnose, galacturonic acid and 3-O-methylgalactose (Beveridge et al. 1971). The polymeric nature of mucilage is composed of polar glycoprotein and dense polysaccharide coatings, which provide its characteristic viscosity and gelling properties (Watts and Rousseau 2012). These pectic polysaccharides are produced by many plants in different organs such as roots, seeds, foliar and inner bark in high concentrations and are assumed to play a role in water and food storage and seed germination (Malviya et al. 2011;Yang et al. 2012). ...
Article
Full-text available
Elms (Ulmus spp.) have long been appreciated for their environmental tolerance, landscape and ornamental value, and the quality of their wood. Although elm trees are extremely hardy against abiotic stresses such as wind and pollution, they are susceptible to attacks of biotic stressors. Over 100 phytopathogens and invertebrate pests are associated with elms: fungi, bacteria and insects like beetles and moths, and to a lesser extent aphids, mites, viruses and nematodes. While the biology of the pathogen and insect vector of the Dutch elm disease has been intensively studied, less attention has been paid so far to the defence mechanisms of elms to other biotic stressors. This review highlights knowledge of direct and indirect elm defences against biotic stressors focusing on morphological, chemical and gene regulation aspects. First, we report how morphological defence mechanisms via barrier formation and vessel occlusion prevent colonisation and spread of wood- and bark-inhabiting fungi and bacteria. Second, we outline how secondary metabolites such as terpenoids (volatile terpenoids, mansonones and triterpenoids) and phenolics (lignans, coumarins, flavonoids) in leaves and bark are involved in constitutive and induced chemical defence mechanisms of elms. Third, we address knowledge on how the molecular regulation of elm defence is orchestrated through the interaction of a huge variety of stress- and defence-related genes. We conclude by pointing to the gaps of knowledge on the chemical and molecular mechanisms of elm defence against pest insects and diseases. An in-depth understanding of defence mechanisms of elms will support the development of sustainable integrated management of pests and diseases attacking elms.
... Experimental data for GERD symptoms are otherwise lacking, though this putative mechanism parallels that of sucralfate and alginate derivates, with the caveat that slippery elm's viscous transformation is not contingent on an acidic milieu. Risks include miscarriage, which necessitates avoidance among women who are or may become pregnant [42]. ...
Article
Full-text available
Purpose of Review Popular remedies are of ongoing interest to patients experiencing common esophageal symptoms, particularly as typical pharmacologic interventions have been subject to increased scrutiny. Herein we summarize the available data regarding potential risks and benefits of several such remedies. Recent Findings With emphasis on reflux and non-cardiac chest pain, research is ongoing into the clinical utility and diverse physiologic mechanisms underlying a variety of complementary and alternative modalities, including dietary manipulation, apple cider vinegar, melatonin, acupuncture, and various herbal products (rikkunshito, STW 5, slippery elm, licorice, and peppermint oil, among others). Summary A substantial gap persists between anecdotal and empirical understandings of the majority of non-pharmacologic remedies for esophageal symptoms. This landscape of popular treatments nevertheless raises several interesting mechanistic hypotheses and compelling opportunities for future research.
... In addition to basic nutritional leaf quality parameters such as contents of water, carbon, nitrogen and protein, we determined the activity of leaf enzymes that can impair protein digestion, that is serine and cysteine proteinase inhibitors (Lawrence & Koundal 2002;Mithöfer & Boland 2012), and activity of enzymes reducing the nutritional quality of plants, that is polyphenol oxidases (Constabel & Barbehenn 2008). Furthermore, we determined the content of mucilage, a polysaccharide and glycoprotein rich substance (Beveridge et al. 1971;Watts & Rousseau 2012). Even though the role of elm leaf mucilage in anti-herbivore defence is yet unknown, its high viscosity might impair feeding activity, especially in young larvae. ...
Article
Full-text available
Plants may take insect eggs on their leaves as a warning of future herbivory and intensify their defence against feeding larvae. Responsible agents are, however, largely unknown, and little knowledge is available on this phenomenon in perennial plants. We investigated how egg deposition affects the anti-herbivore defence of elm against the multivoltine elm leaf beetle. Prior egg deposition caused changes in the quality of feeding-damaged leaves that resulted in increased larval mortality and reduced reproductive capacity of the herbivore by harming especially female larvae. Chemical analyses of primary and secondary leaf metabolites in feeding-damaged, egg-free (F) and feeding-damaged, egg-deposited (EF)-leaves revealed only small differences in concentrations when comparing metabolites singly. However, a pattern-focused analysis showed clearly separable patterns of (F) and (EF)-leaves due to concentration differences in especially nitrogen and phenolics, of which robinin was consumed in greater amounts by larvae on (EF) than on (F)-leaves. Our study shows that insect egg deposition mediates a shift in the quantitative nutritional pattern of feeding-damaged leaves, and thus might limit the herbivore´s population growth by reducing the number of especially female herbivores. This may be a strategy that pays off in a long run particularly in perennial plants against multivoltine herbivores. This article is protected by copyright. All rights reserved.
Article
Full-text available
Drug discovery and development is heavily biased towards the development of monotherapies. Screening, testing, and evaluation of mono-entity drugs are generally much simpler than drug combinations, and are generally easier to get approval from the regulatory authorities for their clinical use. However, monotherapy drugs may not have optimal activity, may have associated toxicities, or may lose activity over time as their target develops resistance. Drug combinations, often developed from existing monotherapies, may have improved efficacy and/or be less toxic. Furthermore, the existing drugs which have lost efficacy due to the development of resistance can often be re-activated by combining them with other chemical entities. Thus, whilst the current climate for drug approval, registration, and clinical use drives the majority of drug development research towards the development of monotherapies, combinations are often a substantial improvement on the original drug. This commentary examines monotherapy and combinational therapy models and discusses the benefits and limitations of each model.
Article
Full-text available
A prior national survey documented the high prevalence and costs of alternative medicine use in the United States in 1990. To document trends in alternative medicine use in the United States between 1990 and 1997. Nationally representative random household telephone surveys using comparable key questions were conducted in 1991 and 1997 measuring utilization in 1990 and 1997, respectively. A total of 1539 adults in 1991 and 2055 in 1997. Prevalence, estimated costs, and disclosure of alternative therapies to physicians. Use of at least 1 of 16 alternative therapies during the previous year increased from 33.8% in 1990 to 42.1% in 1997 (P < or = .001). The therapies increasing the most included herbal medicine, massage, megavitamins, self-help groups, folk remedies, energy healing, and homeopathy. The probability of users visiting an alternative medicine practitioner increased from 36.3% to 46.3% (P = .002). In both surveys alternative therapies were used most frequently for chronic conditions, including back problems, anxiety, depression, and headaches. There was no significant change in disclosure rates between the 2 survey years; 39.8% of alternative therapies were disclosed to physicians in 1990 vs 38.5% in 1997. The percentage of users paying entirely out-of-pocket for services provided by alternative medicine practitioners did not change significantly between 1990 (64.0%) and 1997 (58.3%) (P=.36). Extrapolations to the US population suggest a 47.3% increase in total visits to alternative medicine practitioners, from 427 million in 1990 to 629 million in 1997, thereby exceeding total visits to all US primary care physicians. An estimated 15 million adults in 1997 took prescription medications concurrently with herbal remedies and/or high-dose vitamins (18.4% of all prescription users). Estimated expenditures for alternative medicine professional services increased 45.2% between 1990 and 1997 and were conservatively estimated at $21.2 billion in 1997, with at least $12.2 billion paid out-of-pocket. This exceeds the 1997 out-of-pocket expenditures for all US hospitalizations. Total 1997 out-of-pocket expenditures relating to alternative therapies were conservatively estimated at $27.0 billion, which is comparable with the projected 1997 out-of-pocket expenditures for all US physician services. Alternative medicine use and expenditures increased substantially between 1990 and 1997, attributable primarily to an increase in the proportion of the population seeking alternative therapies, rather than increased visits per patient.
Article
Ulmus parvifolia has been used as a traditional folk medicine to treat the carbuncle in deep skin. In this study, the effect of water extract of root bark of Ulmus parvifolia (WUP) on the carbuncle, pain, inflammation and hypersensitivity was evaluated in animal models. The administration of WUP significantly decreased the size of Staphylococcus aureus (108 cells/mouse)-induced carbuncle, and also exhibited analgesic activity in the HAc-induced writhing syndrome at doses of 50-500 mg/kg. It also showed significant anti-inflammatory activity in the carageenin- and complete Freund's adjuvant-induced inflammation. In the histamine-induced anaphylaxis, it decreased the percent of motality by protecting mice treated with Bordetella pertussis. In the immune responses in the mice sensitized and challenged with sheep red blood cells, the Arthus reaction determined by swelling of foot pad at 4 h after challenge, HA titer, HY titer and PFC which can be used to evaluate the humoral immune response were significantly suppressed by oral administration of WUP at doses of 100 and 200 mg/kg. The cellular immune responses in the same mice such as delayed type hypersensitivity determined by swelling of foot pad at 24 h after challenge and RFC were also significantly suppressed in the same manner.
Article
Communication disorders scientists and practitioners face critical fiscal pressures to establish the efficacy and effectiveness of treatments. The pressures come about from (a) increasing demands from remibursers that a variety of professins test the effectiveness of their treatments, thereby generating demands for the resources to do so; (b) increasing demands for reimbursement of those same clinical services provided by the same variety of professions; and (c) a general recision in in available funds for each. While there is strong evidence that the treatments of speech-language pathologists and audiologists have generally proved potent as they have been tested, the accetped standards for clinical-outcome testing used throughout the research community (e.g. by other clinical disciplines, regulatory agencies of the federal government, and third-party payers) have been mostly ignored. In a marketplace of competition for scare resources, and a recognized set of procedures for demonstrating the efficacy of intervention, it seems obvious that this profession cannot continue to depend on idiosyncratic approaches to clinical-outcome research. Ensuring successful claims for reimbursement requires that assertions of efficacy be justified on the basis of broadly accepted criteria of the general outcome-research community. Critcial aspects of accepted standards are described, including prospective adaptations to the clinical-outcome research of our own discipline. A plausible means for conforming to the standard model is proposed in the context of treatment for aphasia.
Article
Alternative medicine has begun to receive the attention of the legitimate medical community. Recent evidence reveals that 34% of American adults interviewed reported using at least one unconventional therapy during 1994. A 3-month survey of patient inquiries, conducted at The Voice Center, Beth Israel Hospital, Boston, MA, U.S.A. revealed that 41% of patients made inquiries about the potential use of "unconventional approaches" in the management of their voice disorders. Alternative medicine, while largely unproven for efficacy, represents a rapidly growing approach. The present article defines several alternative medical practices, describes their theories and potential impact on the management of voice disorders, and calls for empirical studies to follow. The alternative practices discussed are limited to behavioral therapies such as massage therapy, creative visualization, Alexander, mindfulness, and mediatation.