Articles

Prostate Health

Introduction

The prostate is a walnut-sized organ that lies just below the bladder, surrounding the urethra. The function of the prostate is to enhance the motility of sperm cells by secreting a thin, alkaline fluid into the urethra. Inflammation of the prostate (prostatitis) and benign prostatic hyperplasia (BPH) are common afflictions of men over the age of 50. (1) Prostate cancer is the leading form of cancer among men.

Prostatitis is inflammation caused by an infection of the prostate. Acute bacterial prostatitis is a sudden condition caused by bacterial invasion. Abscesses may form, and the potential for septicemia is high. Chronic bacterial prostatitis can result from enlargement of the prostate and the trapping of bacteria in the urethra. Chronic prostatitis is a major source of urinary tract infections among men.

Benign prostatic hyperplasia (BPH)

Hyperplasia describes the overgrowth of tissue. Benign prostatic hyperplasia is the non-cancerous overproduction of prostate cells, specifically the supporting stromal and glandular tissue, that result in enlargement of the prostate. This condition, which commonly afflicts men over the age of 50, can lead to a range of uncomfortable symptoms and increases the propensity toward bladder infections. The exact mechanism that stimulates prostatic hyperplasia is not completely understood. Hormonal changes are thought to play a significant role. As men age, testosterone levels drop and a metabolite of testosterone, dihydrotestosterone (DHT) rises. It is thought that DHT plays a role in prostate enlargement by stimulating cellular growth. DHT also increases mitochondrial activity and alters cellular glutathione peroxidase in prostate cells, inducing oxidative stress. (2) There is evidence that increased estrogen levels are responsible for prostatic hyperplasia and enlargement. (3) Testosterone is converted to estradiol by the enzyme aromatase. This occurs in the liver and adipose tissue. Since fat stores commonly increase with age, it is possible that the incidence of prostate disease is correlated with body fat. (4)

Prostate cancer

Prostate cancer is the most common form of cancer in men. It is primarily diagnosed in men over 65, although it may begin much earlier. It is a very slow growing form of cancer. Prostate cancer often metastasizes to other tissue, including the brain, lungs, lymph nodes, and bones. Early detection is critical in order to increase the chances for survival. The cancer can be palpated upon digital rectal examinations. These examinations are recommended routinely for all men over the age of 40.

Statistic

National Vital Statistics Reports, Vol. 48, No. 11.

    The annual number of deaths from Prostate Cancer are 32,203 (1998).

Vital and Health Statistics Series 10, No. 200.

    Cases of Prostate Disease Reported Annually: 2.8 million (1996).

Vital and Health Statistics Series 13, No. 143.

    Number of Ambulatory Care Visits for Prostate Cancer: 2.5 million (1997).

Campbell's Urology (7th ed.). Philadelphia: W. B. Saunders Company.

    The prevalence of Enlarged Prostate (BPH) is more than 50 percent of men age 51-60; 90 percent of men past age 80. The number of hospital discharges involving a diagnosis of BPH (1996) were 351,000 hospitalizations.

Signs and Symptoms

[span class=alert]The following list does not insure the presence of this health condition. Please see the text and your healthcare professional for more information.[/span]

Acute prostatitis is characterized by a sudden onset of fever, chills, lower back pain, and perineal pain. Urinary burning with frequency, urgency, and nocturia are common. Chronic prostatitis produces milder symptoms, including frequency, urgency, dysuria, and discharge.

The beginning stages of BPH are asymptomatic. As the condition worsens, the enlarged prostate obstructs the urethra, leading to painful and difficult urination. The primary symptoms include the frequent urge to urinate, nocturia, difficulty starting urination, reduced force of the stream, dribbling after urination, and incomplete emptying of the bladder. The stagnation of urine in the bladder predisposes those with BPH to persistent bladder infections.

Early stages of prostate cancer are asymptomatic. Obstructive symptoms occur later in the disease. Difficulty urinating, frequency, urinary retention, and diminished force of the urine stream are characteristic symptoms. If the cancer has spread, symptoms may include fatigue, nausea, weakness, back pain, swollen lymph nodes, discomfort in the perineum, hip pain, or weight loss. Blood may be present in the urine.

Acute prostatitis

    Sudden onset of fever Chills Lower back pain Perineal pain Urinary burning with frequency, urgency, and nocturia

Chronic prostatitis

    Increase in urinary frequency Increase in urinary urgency Dysuria Penile discharge

Benign Prostatic Hypertrophy

    Initial stages asymptomatic Increased urgency to urinate Nocturia Difficulty initiating urination Reduced force of urine stream Dribbling Incomplete bladder emptying May present persistent bladder infections

Prostate cancer

    Initial stages are asymptomatic Difficulty urinating Urinary retention Diminished force of the urine stream Fatigue Nausea Weakness Back pain Swollen lymph nodes Discomfort in the perineum Hip pain Weight loss Hematuria

Treatment Options

Conventional

Treatment for acute prostatitis is directed toward preventing abscesses and septicemia. Since there is poor infusion of drugs from the blood into the prostate fluid, treatment is challenging. High doses of broad- spectrum antibiotics are given orally for up to two weeks. If the condition does not improve, intravenous administration may be necessary. Treatment of chronic prostatitis is primarily symptomatic. If urinary tract infection occurs, antibiotics are given. Sometimes low doses of antibiotics are given prophylactically over an extended period to prevent urinary tract infections.

    5 a-reductase inhibitors block the action of 5a-reductase, the enzyme that converts testosterone to dihydrotestosterone. Finasteride (Proscar) suppresses serum DHT by about 70 percent, and prostate DHT by 85 to 90 percent. (5) Proscar works by inhibiting the type II 5a- reductase found primarily in genital tissue. Improvement of symptoms generally takes three to twelve months, and the drug must be taken for life to maintain its effects. (6) It has been demonstrated that 5a-reductase inhibitors perform best among men with prostates at least 40 grams, and especially in men with prostates 50 grams or larger. (7) Alpha-adrenergic blocking agents relax the smooth muscle of the urethra and bladder, making urination easier. Terasozin (Hytrin), doxasozin (Cardura), and prazosin (Minipress) are examples of drugs in this class. Alpha-blockers are also used to treat high blood pressure. Under the influence of alpha-blockers, arterioles and veins are dilated, peripheral resistance is reduced, and blood pressure is decreased. Potential side effects include orthostatic hypotension, weakness, fatigue, drowsiness, nausea, blurred vision, weight gain, and edema. The newest alpha-blocking agent, tamsulosin (Flomax) works in a similar fashion to the other drugs of this class, but with lower risk of orthostatic hypotension. Flomax is not associated with first-dose syncope found with other alpha-blockers, and therefore does not require dose titration. (8) If symptoms do not respond to pharmacotherapy, or if urination is completely obstructed, surgery may be indicated.

Treatment of prostate cancer is determined by the stage of the disease. If the cancer is limited to the prostate, radical prostatectomy is usually performed, with or without radiation therapy. A recent study found, however, that men who had their prostates removed after diagnosis did not survive appreciably longer than those who’s cancers were monitored without intervention. (9) For later stages, treatment is palliative. Hormonal therapy with estrogens may be used to suppress all andronergic activity in the prostate. Orchiectomy may be considered, as over 90 percent of testosterone originates in the testicles.

Nutritional Supplementation


Zinc

The prostate gland stores zinc and the concentration of zinc in the prostate gland is much higher than in other tissues in the human body. (10) Adequate zinc levels help to prevent enlargement of the prostate gland. This is because zinc influences the activity of the 5 alpha-reductase enzyme. When zinc levels are low, the activity of this enzyme is higher, causing a greater conversion of testosterone to dihydrotestosterone (DHT). On the other hand, when zinc levels are higher the activity of 5 alpha-reductase is reduced, and there is less conversion of testosterone to DHT. (11) Zinc not only prevents prostate enlargement; animal studies report it may also help to shrink a gland that is already swollen. (12)

Taking zinc alone isn’t enough to insure prostate health. Vitamin B6 influences zinc absorption. Apparently vitamin B6 helps to convert zinc to a form that is more absorbable by the tissues in the prostate. (13) Studies indicate that vitamin B6 is deficient in the diet of many Americans, which may be contributing to low zinc status and increased prostate problems. For example, data from the Second National Health and Nutrition Examination Survey (NHANES II) reported that 71% of males consumed less than the RDA for vitamin B6 on a daily basis. (14)


Lycopene

Lycopene is a dietary component that seems to provide specific protection against prostate cancer. Results from the Health Professionals Follow-Up Study reported a lower prostate cancer risk among men who consumed larger quantities of tomatoes and related lycopene-containing food products. (15) In another study, significantly lower serum and tissue lycopene levels were observed in men with prostate cancer compared to controls. (16)

Tomatoes are the primary dietary source of lycopene and it has been reported that lycopene is one of the most effective quenchers of the singlet oxygen free radical. It is interesting to note that the highest concentrations of lycopene occur in the testes, adrenals, and prostate gland. (17) Lycopene concentration is highest in cooked tomato products. It is estimated that a minimum of 4-6mg daily intake of lycopene is needed for prostate protection.


Selenium

The following study suggests that selenium supplementation may provide significant protection against prostate cancer. This was initially a study to evaluate whether or not selenium supplementation could reduce the reoccurrence of either basal cell or squamous cell carcinoma. Where 974 men were randomized to receive either a daily supplement of 200mcg of selenium or a placebo. These men were treated for an average of 4.5 years and then followed for an additional 6.5 years.

Evaluation of secondary endpoints in men that initially had normal PSA levels revealed that selenium supplementation was responsible for a 63% reduction in the incidence of prostate cancer. Four men were diagnosed in the selenium-treated group, compared to 16 cases of prostate cancer in the placebo group. Compared to placebo controls, the individuals taking selenium also had significant reductions in colorectal cancer and lung cancer. (18)


Vitamin E

The results of a controlled study that evaluated the incidence of prostate cancer and deaths among 29133 male smokers aged 50-69 years who took vitamin E indicated that men taking 50mg of vitamin E daily had a 32 percent lower incidence of prostate cancer, and a 41 percent reduction in deaths from prostate cancer. (19) In a similar study, among current smokers and recent quitters, men who consumed at least 100 IU of supplemental vitamin E per day had a significant reduction in the risk for metastatic or fatal prostate cancer compared with nonusers of supplemental vitamin E. (20)

Herbal Supplementation


Saw Palmetto

Saw palmetto is used in men suffering from benign prostatic hyperplasia (BPH). (21) , (22) , (23) Several studies have reported the effects of saw palmetto as being as least as good as the common drugs used to treat BPH. (24) , (25) It has also been recommended for nocturnal enuresis and other urinary tract disorders. (26) Benign prostatic hyperplasia (BPH) is thought to be caused by an increase in the conversion of testosterone to 5-a dihydrotestosterone (DHT) in the prostate. (27) DHT stimulates the production of prostate cells. Excessive formation of DHT leads to overproduction and enlargement of the prostate (hyperplasia). Another factor is the presence of estrogen which inhibits the elimination of DHT. There are several reported mechanisms of action of saw palmetto for use in treating BPH. They include inhibition of DHT production, inhibition of the binding of DHT to its receptors and promoting its breakdown. (28) , (29) , (30) Pretreatment of saw palmetto to patients with benign prostatic hyperplasia undergoing a transurethral resection of prostate operation seemed to have improved efficacy of the procedure itself and experienced a reduced risk of complications. (31)

Also, saw palmetto is reported to exert an antiestrogenic effect, as well as an antiandrogenic effect. (32) Some investigators believe that its antiestrogenic effect may be more important than any of its other actions. Saw palmetto inhibits 5-a reductase, an enzyme that catalyzes the conversion of testosterone into DHT, having alpha-1 and alpha-2 adrenergic blocking capabilities. (33) , (34) Various clinical studies have reported the positive benefits of using standardized saw palmetto extracts in the prevention of BPH, and saw palmetto has compared favorably with finasteride in several studies. (35)


Pygeum

Pygeum grows mainly in Southern Africa, Madagascar, and some areas of Central America. Today, a lipophilic extract is used and confirmed as a treatment for benign prostatic hyperplasia (BPH). Pygeum bark is currently indicated for benign prostatic hyperplasia, dysuria, diurnal and nocturnal pollakiuria, prostatitis and prostatosis, and adenomatous fibrosclerosis. (36) Pygeum is reported to improve prostate functionality through a hormonal-like mechanism and reduces the inflammation often connected with BPH.

There are several classes of compounds in pygeum that can interfere with the development of BPH, with each compound exhibiting different but complementary pharmacodynamic effects. The classes of bio-active components are the phytosterols, the esters of fatty alcohols with ferulic acid and the pentacyclic terpenes. The phytosterols, present in free and conjugated form, are reported to be competitive with endogenous and exogenous precursors of androgenic hormones (such as DHT), decreasing exposure of the prostatic cells to hormonal stimulation. (37) b-sitosterol and it's glucoside posses anti-inflammatory properties on prostatic tissue, medicated by inhibition of prostaglandins PGE2 and PGF2a biosynthesis. (38) The prostaglandin content is considerable increased in prostatic tissue in patients with BPH.

In animal experiments, extracts of pygeum have reported improvement in prostate function as confirmed by histological examination of the glandular portion. (39) Over 26 open and double blind clinical trials have been perfomed using pygeum bark extracts in the management and treatment of BPH, totaling over 721 patients to date. (40) , (41) In one of the studies (Breza, et al., 1998) of patients with symptoms of BPH, nocturnal frequency was reduced by 32% and the mean reduction was highly statistically significant. Mean maximum urinary flow, average urinary flow, and urine volume were also statistically significantly improved, but the modest improvement in post-voiding volume did not reach statistical significance. The improvements, which exceeded those observed with placebo in earlier studies, were maintained after one month without treatment indicating an interesting persistence of clinically useful activity. Prostatic volume and quality of sexual life remained unchanged throughout. No treatment-related adverse effects were observed. Pygeum has been combined with stinging nettle root (Urtica dioica) for patients with BPH with positive clinical results. (42)


Stinging Nettle

Stinging nettle root has been reported to be beneficial in the treatment of benign prostatic hyperplasia (BPH). (43) , (44) Stinging nettle root is reported to inhibit sex hormone binding globulin which has an effect on the androgenic receptors of the prostatic cytosol and inhibits the effects of estrogen. (45) , (46) It is also reported to influence the binding of 5 alpha-dihydrotestosterone with its receptors. (47) , (48)

Acupuncture & Acupressure

Treatment with acupuncture and moxibustion
Otopuncture was used to treat 14 cases of prostatic hyperplasia. Otopoints related to the following areas were used: the pelvic cavity, prostate, kidney, liver, bladder, spleen, brain point, and sympathetic nerve. The needles were manipulated to assert moderate stimulation and were retained for 40 minutes. The results: 9 cases recovered, 4 cases improved, and 1 case did not respond to the treatment. (49)

Acupuncture and ginger moxibustion were jointly used to treat 38 cases of prostatic hyperplasia. Patients with yang deficiency of the spleen and kidney and with bladder dysfunction in qi transformation received acupuncture treatment on Guan Yuan (Ren 4), Zu San Li (St 36), San Yin Jiao (Sp 6), Pang Guang Shu (UB 28), Shen Shu (UB 23), and Pi Shu (UB 20). The needles were vertically inserted into the acupoints and were retained while ginger moxibustion was applied (three moxa cones). Patients with yin deficiency of the liver and kidney and with downward flow of damp-heat into the bladder received acupuncture treatment on Zhong Ji (Ren 3), Tai Chong (Liv 3), San Yin Jiao (Sp 6), Pang Guang Shu (UB 28), Shen Shu (UB 23), and Gan Shu (UB 18). Using the reinforcing-reducing method, the acupuncture treatment was conducted daily, and 10 sessions constituted one course of treatment. The results: 10 cases recovered, 24 cases improved, and 4 cases did not respond to the treatment. (50)

Fresh-water turtle shell moxibustion was used to treat 65 cases of prostatic hyperplasia. A whole fresh-water turtle shell was washed clean, air-dried, and soaked in hydrochloric acid (1:1500) for an hour. Several cloves of garlic were spread out on acupoint Zhong Ji (Ren 3) and covered with the treated turtle shell. A 2mm-thick mugwort floss was placed on the shell, and ignited and burnt. Right after this treatment, the acupoint was palm-massaged for three minutes. The moxibustion was repeated 2 times a day, and one course of treatment lasted 10 days. The results: after one course of treatment, 35 cases significantly improved, 29 cases improved, and 1 case did not respond to the treatment. (51)

Traditional Chinese Medicine

Prostate Health

Extensive information regarding the treatment of this health condition using Traditional Chinese Medicine is available through the link above.

Diet & Lifestyle

Dietary fat: There are many studies that discuss how various factors related to diet and nutrition influence cancer. Although only a small amount of this research relates directly to the prevention or treatment of prostate cancer, the following reviews what has been reported.

Most studies that have evaluated the relationship between dietary fat and prostate cancer report that diets high in total fat are associated with an increased rate of prostate cancer. (52) , (53) Even though there are some inconsistencies, there is the suggestion that diets high in saturated fat and/or animal fat increase the risk of prostate cancer. (54) , (55) In studies on dietary meat intake, three of four cohort studies and four of five case-control studies report an increased risk of prostate cancer with higher meat consumption.

Clinical Lab Assessment

Some of the following laboratory testing can provide information necessary for diagnosis and treatment. In addition, the tests listed may also give insight to functional metabolism and functional nutrient status in the body.

Hormone Assessment

    Estrogen, Progesterone and Testosterone: Estradiol increases a genetic product (Bcl-2) that leads to cell proliferation and delay in apoptosis, both of which increase cancer risk. Progesterone suppresses Bcl-2 action and increases another genetic control product (p53) that slows cell proliferation and restores proper apoptosis, both of which decrease cancer risk. (56) Testosterone (but not the DHT) stops cancer cell growth. Assessment of these hormones may be useful.

Prostate Specific Antigen (PSA)

This glycoprotein, exclusive to the prostate epithelium, is a smaller, more stable molecule than PAP and does not demonstrate diurnal fluctuations. PSA is used as a marker for the detection of prostate cancer.

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