SUMMARIES OF RESEARCH ON STEROLS AND
STEROLINS
Antihyperglycemic and insulin-releasing
effects of B-sitosterol 3-B-D-glucoside and Its aglycone, B-sitosterol
Author: M.D. Ivorra, M.P. D'Ocon M. Paya and A. Villar
Source: Archives of the Intemational Phamnacodyn, v.296,pp.224-231, Aprii 1988
An animal experiment was performed to determine the effects of the phytosterols,
B-sitosterol and its glucoside, B-sitosterolin on plasma insulin and glucose
levels in normal and hyperglycemic rats. The results indicate that when either
phytosterol was administered orally, it increased the fasting insulin levels and
lowered, the fasting glucose levels. In an oral glucose tolerance test, the
phytosterols protected the animal from an excessive rise in serum glucose levels
due to the glucose loading. The results indicated that the B-sitosterol was more
active over time in moderating glucose levels than the glucoside, B-sitosterolin.
The anti-hyperglycemic effect of the sterols and sterolins are thought to be due
to an increase in circulating insulin levels which is attributable to a
stimulation of insulin secretion from pancreatic B-cells. These results indicate
a possible anti-hyperglycemic use for the phytosterols in the prevention and
treatment of pre-diabetic and diabetic conditions.
Anti-inflammatory and antipyretic activities of B-sitosterol
Author: M. B. Gupta, R. Nath, N. Srivastava, K. Shanker, K. Kishor and K.P.
Bharguva
Source: Planta medica (Jouma/ of Medicinal Plant Research) v.39,pp.157-163, 1980
A basic research study using animal experiments was performed to determine
whether sterols (plant fats) had any therapeutic properties such as reducing
inflammation (antiinflammatory), reducing fever (antipyretic) and reducing pain
(analgesic). An extract of sterols from the seeds of the Indian herbal plant
Cyperus rotundus was used in three separate experiments with rats to aetermine
the medicinal properties. It was demonstrated that sterols possess potent
antiinflammatory properties s,milar to cortisone. Sterols were also demonstrated
to reduce experimentally-produced edema. Sterols were also shown to have
fever-reducing properties similar to aspirin (ASA). However, the sterols did not
possess any pain-reducing or analgesic properties. In separate toxicology tests,
sterols were shown to possess a very large margin of safety and produced minimal
side effects such as gastric ulceration. The study concluded that sterois
possess highly potent anti-inflammatory and antipyretic actions with a high
margin of safety, sucgesting its application to human medicine.
An immunoendocrinological hypothesis of HIV infection
Author M. Clerici, M. Bevilacqua, T: Vago, M. L. Villa, G.M. Shearer & G.
Norbiato
Source: Lancet, v. 343, pp. 1552-1553, June 18, 1994
This paper advances the hypothesis that the progression of AIDS and the
dysreguiation of the immune system may be due to the immunosuppressive effects
of increased cortisol levels and a decrease of DHEA levels resulting in an
increased cortisol/DHEA ratio. Patients with AIDS have been observed to have a
shift from type-1 to type-2 production of the immune mediators called cytokines.
A reduction of Th1 lymphocytes results in the progressive reduction of
interleukin-2, interleukin-12, and gamms interferon which are cytokines
controlling cell-mediated immunity. Celt-mediated immunity is responsible for
the control of pathogens such as viruses. At the same time Th2 lymphocytes,
which stimulate humoral immunity through the secretion of the cytokines
interleukin-4, interleukin-6 and interlaukin-10, are increased in AIDS patients.
Normally, these two cytokine subsets promote their own secretion and su;,press
the other cell line, resulting in a homeostasis between these two cell lines of
the lymphocytes in AIDS patients, there is a shift to type-1 suppression and
type-2 dominance, thus destroying the equilibrium of the immune system. It is
postulated that the Th2 cell lines are B-cells which are natu,ally more
resistant to HIV infection. The decline of the The. lymphocytes results in the
devastating loss of the cell-mediated immune response, resulting in an
uncontrollable increase of HlV-infected cells. It is thought that the increase
in the cortisol/DHEA ratio selectively suppresses the production of type-1
cytokines and favors the production of type-2 cytokines. This results in the
unfortunate crippling of the immune system and a decrease in cell-mediated
immunity due to increased apoptosis of both CD4 and CD8 cells. A therapeutic
strategy is suggested that by controlling the cortisol/DHEA ratio, one can
reduce the overproduction of type-2 cytokines and promote the secretion of
type-1 cytokines. This would result in the restoration of immune balance and
stop the progression of the HIV infection and the AIDS sequelae.
The importance of sitosterol and sitosterolin in human and animal nutrition
Author: Karl H. Pegel, Department of Chemistry and Applied Chemistry,
University of Natal, Durban, South Africa.
Source: South African Joumal of Science, v. 93, pp. 263-268, June.1997
Recent research indicates that the health-promoting benefits of a plant-based
diet may be due to the presence of plantderived cholesterol analogs known as
sterols and sterolins. These compounds, which are structurally similar to
cholesterol, are ubiquitous throughout the plant kingdom. Although absorbed at a
rate 800 to 1,000 times less than cholesterol, they appear to have important
immuno-modulatory and anti-inflammatory activities in human and animal
physiology. Human research indicates plant sterols and sterolins have important
anti-inflammatory, anti-ulcer, anti-diabetic, anticancer and T-cell
proliferative activities. Medical uses already include the treatment of hyper-cholesterolemia,
benign prostatic hypertrophy and ,rheumatoid arthritis. Plant sterols and
sterolins are thought to be responsible for the health benefits of a variety of
medicinal herbs including saw palmetto, pygeum, pumpkin seeds, devil's claw,
milk thistle, ginkgo, Panax and Siberian ginseng. They have adaptogenic
properties which make them an essent al part of an optimal diet. Modern food
processing and dietary choices have resulted in a daily intake less than the
optimal '200-300 mg. Even some vegetarian diets appear to result in a deficient
quantity of plant sterois and sterolins. Supplementation of the diet with plant
sterols and sterolins provides important therapeutic as well as preventative
health benefits.
Interleukins and the immune system
Author: Anne O'Garra Source: Lancet, v. 1, 8644, pp. 943-946, 1989
The immune response has two ways of dealing with foreign pathogens. The
B-lymphocytes synthesize specific antibodies called immunoglobulins. This is
known as humoral immunity. The other system involves T-lymphocytes which
regulate the synthesis of antibodies as well as direct killer cell activity and
the inflammatory response of delayed type hypersensitivity. This system is known
as cell-mediated immunity. The T-cells are further divided into helper
lymphocytes (Th) and cytotoxic (Tc), also known as suppressor cells. When the
T-cells encounter a foreign pathogen (antigen) they further secrete a number of
communication molecules called Iymphokines, cytokines, interleukins or
interferons. These factors further elaborate and direct the immune response to a
specific antigen. The whole process is a symphony of many cofactors which are
orchestrated into a sophisticated immune response. The T-helpar cells are
directly involved in assisting B-cells as well as co-ordinating their own
cell-specific defense. The T-helper cells are further divided into two distinct
lines of defense. The Th1 cells promote the cell-mediated line of defense and
inhibit the other line known as Th2 cells which regulate the humoral defense.
The Th2 cell lines control the B-cells and inhibit the cell-mediated response of
the Th1 lymphocytes. A careful balance between these two functions is thus
achieved. When one line predominates, there is the opportunity for immune
dysregulation to occur resulting in either a hyper-immune response causing an
autoimmune disease or a hypo-imrnune response resulting in an uncontrollable
infection such as AIDS or tuberculosis. The Th1 helper cells secrete
Iyrnphokines such as interleukin-2 and gamma interferon. Th2 helper cells
secrete pro-inflammatory Iymphokines such as nterleukin-6, interleukin-4 and
interleukin-10. Interleukin-l appears to be released in response to a specific
injury and acts as an inflammatory mediator. Interleukin may be over-expressed
in diseases such as rheumatoid arthritis and osteoarthritis. Interleukin-1
deficiency is associated with metastatic tumors, nutritional deficiencies and
certain autoimmune diseases. Interleukin-6 is associated with pro-inflammatory
responses as well as mediating the proliferation and matulation of T-cells. High
levels of interleukin-6 have been associated with a variety of autoimmune
conditions such as rheumatoid arthritis, Sjogren's syndrome, multiple myelomas,
and some cancers such as cervical and bladder. Interleukin-2 is a growth factor
for T-cell maturation as well as an inducer of T-cell cytotoxicity and natural
killer cell activity. Interleukin-2 deficiency would cripple the cellmediated
immune response and its stimulation would enhance the overall efficacy of the
immune system. Immune dysregulation occurs when the two sides of the immune
response become imbaianced. A greater appreciation of immunotherapies is
achieved with a more detailed understanding of the complexity of the immune
system.
A multicentric, placebo-controlled, double-blind clinical trial of beta-sitosterol
(phytosterol) for the treatment of benign prostatic hyperplasia
Author: Klippel K.F.; Hiltl D.M.; Schipp B. (German BPH-Phyto Study group.)
Source: British Jouma/ of Urology, v. 80(3), pp. 427-32, Sept. 1997
This randomized placebo-controlled study involved 177 patients with an enlarged
prostate gland (benign prostatic hyperplasia). This study was designed to asses
the safety and efficacy of using b-sitosterol in treating this condition. Over
the 6 month duration of this study individuals received 130 mg of b-sitosterol
daily. Parameters used to monitor the effectiveness of this novel treatment
approach included postvoid residual urinary flow rate (PVR), peak urinary flow
rate (Qmax), and qualitative determinators provided by the inter- national
prostate symptom scores (IPSS) and changes in the quality of life index value.
Statistically significant results over the placebo control were noted. Qmax
values increased by 4.5 ml while improved PVR values were noted (decrease of
33.5 ml). Quality of life scores and IPSS values also showed a statistically
significant improvement. These results indicate that b-sitosterol is in fact an
effective treatment option for individuals with BPH.
Randomized, placebo-controlled, double-blind clinical trial of B-sitosterol
in patients with benign prostatic hyperplasia
Author: R.R. Berges, J. Windeler, H.J. Trampisch, T.H. Senge and the b-sitosterol
study group
Source: Lancet v. 345, no. 8964, pp. 1529-32, June 1995
This is a randomized, double-blind, placebo-controlled, multi-center study of
200 men with BPH (benign prostatic hyperplasia) treated with the phytosterol, B-sitosterol.
Two hundred men were selected and followed for 6 months using a variety of lab
tests, and subjective and objective symptom indicators for BPH. Half the group
received the active treatment, 20 mg B-sitosterol three times daily and the
other half received the placebo. The results indicate that the group treated
with B-sitosterol improved in both subjective symptoms of BPH and the objective
measurement of improved urine flow. These results occurred independent of a
reduction in tual prostate size. Only minor side effects were observed with the
phytosterol treatment group compared to the more toxic side effects associated
with the 5-alpha-reductase inhibitor drugs such as finaseride. No mechanism for
the effects of B-sitosterol on the prostate has been elucidated as yet. This
study indicates the traditional herbal treatment of BPH with saw palmetto,
Pyceum africanus and pumpkin seeds may be attributable tc the phytosterol
content of these herbs. A German herbal preparation sold for the last 20 years
under the trade name Harzcl for the treatment of BPH contains a mixture of
phytosterols including B-sitosterol.
Sterol content of foods of plant origin
Author Weihrauch J. L., Gardner J. M.
Source: Joumal of the American Dietetic Association, v. 73, pp.39-47, July 1978
Available data on phytosterols from the world's literature have been compiled
and summanzed. There still exists a paucity of data on the quantities of plant
sterols in many foods. More extensive data are available on the relative sterol
compositions. Our compilation shows that plant oils are excellent sources of
phytosterols. Nuts and seeds contain moderate levels, and fruits and vegetables
generally contain the lowest concentrations of plant sterols. Analysis of the
minor sterols, namely, the delta5- and delta7-phytosterols, have become vailable
only recently.
Disclaimer: These Articles and or
information are not intended to mitigate the symptoms or cure the specific
diagnosis of cancer or cancer related disease states.
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