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Biochimica et Biophysica Acta | 1984

Reduction of lecithin-cholesterol acyltransferase, apolipoprotein D and the Lp(a) lipoprotein with the anabolic steroid stanozolol

John J. Albers; Hugh McA. Taggart; Deborah Applebaum-Bowden; Steven M. Haffner; Charles H. Chesnut; William R. Hazzard

The effects of the anabolic steroid stanozolol (17-methyl-2H-5 alpha-androst-2-eno-(3,2-c)pyrazol-17 beta-ol) on lecithin-cholesterol acyltransferase, apolipoproteins B and D and the Lp(a) lipoprotein were determined in a prospective study of ten normolipidemic women with postmenopausal osteoporosis. Lecithin-cholesterol acyltransferase was reduced approx. 30% by 6 weeks of treatment with stanozolol (off treatment 5.1 +/- 1.2, on treatment 3.4 +/- 0.8 muml; P less than 0.02). The Lp(a) lipoprotein was reduced 65 +/- 23% by the steroid treatment (off treatment 5.5 +/- 5.5, on treatment 1.4 +/- 0.7 mg/dl; P less than 0.02). Apolipoprotein D was reduced 23 +/- 9% by the treatment (off treatment 5.9 +/- 0.9, on treatment 4.5 +/- 0.7 mg/dl; P less than 0.02). In contrast, apolipoprotein B increased slightly but insignificantly on steroid therapy (off treatment 90 +/- 21, on treatment 112 +/- 24 mg/dl). By 5 weeks after the drug was discontinued, all four of these proteins were near pretreatment levels. These significant changes in lipoprotein metabolism, combined with our previous report of reductions of HDL and particularly HDL2, suggest the need for caution in the long-term use of anabolic steroids.


Metabolism-clinical and Experimental | 1983

Studies on the metabolic mechanism of reduced high density lipoproteins during anabolic steroid therapy

Steven M. Haffner; Rampratap S. Kushwaha; David M. Foster; Deborah Applebaum-Bowden; William R. Hazzard

To explore the mechanism whereby stanozolol, a 17 alpha-methyl androgenic anabolic steroid, depresses high density lipoproteins (HDL), 6 subjects, aged 46-71 yr (4 postmenopausal women and 2 men), underwent paired studies of 125I-HDL turnover (including HDL2 and HDL3 and Apo A-I and A-II) and postheparin plasma (PHP) lipolytic activity (hepatic triglyceride lipase, HTGL, and lipoprotein lipase LPL) before and during treatment with stanozolol, 6 mg/day. While total cholesterol and triglyceride levels did not change during stanozolol, HDL-cholesterol decreased from 59 +/- 18 mg/dl (x +/- SD) to 29 +/- 7 mg/dl (p less than 0.01) and low density lipoprotein (LDL)-cholesterol increased from 160 +/- 36 mg/dl to 181 +/- 42 mg/dl (p less than 0.02). PHP-HTGL increased from 111 +/- 47 nmole/min/ml to 369 +/- 202 nmole/min/ml (p less than 0.04), while PHP-LPL did not change. At baseline the residence time of HDL2 (4.00 +/- 1.04 day) was shorter than that of HDL3 (6.79 +/- 1.00 day) (p less than 0.001). Residence times of both declined on stanozolol, to 3.25 +/- 0.83 day and 4.00 +/- 0.29 day, respectively (0.1 less than p less than 0.2); however, only the reduction in residence time of HDL3 was statistically significant (p less than 0.001). At baseline the residence time of apo A-I (4.93 +/- 1.32 day) was shorter than that of A-II (6.85 +/- 1.98 day) (p less than 0.025); on stanozolol these declined to 3.19 +/- 0.41 (p less than 0.02) and 5.10 +/- 1.13 (p = 0.07), respectively, still significantly different from each other (p less than 0.005).(ABSTRACT TRUNCATED AT 250 WORDS)


Metabolism-clinical and Experimental | 1982

Reduction in high density lipoproteins by anabolic steroid (stanozolol) therapy for postmenopausal osteoporosis.

Hugh McA. Taggart; Deborah Applebaum-Bowden; Steven M. Haffner; G.Russell Warnick; Marian C. Cheung; John J. Albers; Charles H. Chestnut; William R. Hazzard

The effects of stanozolol, 17-methyl-2H-5 alpha-androst-2-eno [3,2-c] pyrazol-17 beta-ol, on lipoprotein levels were assessed in a short-term (6 wk) prospective study of 10 normolipidemic, postmenopausal, osteoporotic women. While total cholesterol and triglyceride levels remained constant, equal and offsetting responses were seen in low density lipoprotein (LDL) cholesterol (+30.9 +/- 28.1 mg/dl [mean +/- S.D.], p less than 0.01, a 21% increase) and high density lipoprotein (HDL) cholesterol (-32.5 +/- 11.9 mg/dl [mean +/- S.D.], p less than 0.001, a 53% decline). Hence the LDL/HDL ratio increased dramatically, from 2.5 +/- 0.7 to 6.8 +/- 2.5. Within HDL, stanozolol was associated with a greater decline in HDL2 (from 26.0 +/- 7.4 mg/dl to 3.8 +/- 1.9 mg/dl, p less than 0.001, an 85% decrease) than HDL3 (which diminished from 35.7 +/- 3.2 to 24.1 +/- 5.8 mg/dl. p less than 0.001, a 35% decrease). The major HLD apolipoproteins also declined (A-I by a mean of 41% and A-II by 24%, both p less than 0.001). Postheparin hepatic triglyceride lipase increased (off treatment 74 +/- 42 nmole free fatty acid min-1 mole-1, on treatment 242 +/- 110, n = 6, p = 0.06). All changes were reversed by 5 wk following termination of the drug. These lipoprotein changes suggest caution in the long term prescription of stanozolol, particularly in those without overriding clinical indications for its use.


Arteriosclerosis, Thrombosis, and Vascular Biology | 1985

Postheparin plasma triglyceride lipases. Relationships with very low density lipoprotein triglyceride and high density lipoprotein2 cholesterol.

Deborah Applebaum-Bowden; Steven M. Haffner; Patricia W. Wahl; J J Hoover; G R Warnick; John J. Albers; W R Hazzard

Hepatic triglyceride lipase (HTGL) and lipoprotein lipase (LPL) probably have major roles in the removal of triglyceride from triglyceride-rich lipoproteins and in the formation of high density lipoprotein (HDL). However, no population-based study of their activity and relationship to lipoprotein lipid levels has been reported. To determine these relationships, we recalled 33 men and 17 women of a randomly selected sample of the Lipid Research Clinics Pacific Northwest Bell Telephone Company Health Survey. The subjects were 53 ± 7 years old (mean ± SD) with total triglyceride levels of 120 ± 57 mg/dl and total cholesterol levels of 224 ± 35 mg/dl. Postheparin plasma LPL activity (127 ± 61 nmol/min/ml) was not significantly correlated with either age, sex, or adiposity. In contrast, HTGL activity was significantly higher in men (235 ± 84 nmol/min/ml) than women (170 ± 91 nmol/min/ml, p < 0.02), and was correlated with age in men and with adiposity in women. In both men and women, HTGL activity was related positively with VLDL triglyceride and inversely with HDL2 cholesterol. When the association between HTGL activity and VLDL triglyceride was examined with values from men and women pooled, the relationship was not weakened after adjustment for the linear effect of sex, adiposity, LPL, or HDL2 cholesterol.


Arteriosclerosis, Thrombosis, and Vascular Biology | 1985

Epidemiological correlates of high density lipoprotein subfractions, apolipoproteins A-I, A-II, and D, and lecithin cholesterol acyltransferase. Effects of smoking, alcohol, and adiposity.

Steven M. Haffner; Deborah Applebaum-Bowden; Patricia W. Wahl; J J Hoover; G R Warnick; John J. Albers; W R Hazzard

Recent data suggest that the protection against ischemic heart disease afforded by high density lipoprotein (HDL) cholesterol (C) may be concentrated in the HDL2 subfraction. To examine the behavioral correlates of the HDL subfractions, we recalled 33 men and 17 women of a random sample from the Pacific Northwest Bell Telephone Company Health Survey. Adiposity and very low density lipoprotein (VLDL) triglyceride were negatively correlated with HDL2C. Smoking was not correlated with HDL2C, but was negatively correlated with HDL3C (men, rs = −0.635, p = 0.001; women, rs = −0.534, p 0.014); this relationship was independent of alcohol consumption, adiposity, and VLDL triglyceride. Alcohol consumption was also more strongly related to HDL3C (men, rs = 0.248, p = 0.082; women, rs = 0.586, p = 0.007). Lecithin cholesterol acyltransferase (LCAT) mass was negatively related with HDL2C, but was positively correlated with HDL3C and apolipoprotein A-II. Smoking was negatively correlated with LCAT mass. Since it is believed that HDL3C is not associated with the risk of ischemic heart disease and since both smoking and alcohol consumption may mainly affect HDL3C, the current study suggests that the increase in risk of ischemic heart disease with smoking and the possible decrease with alcohol consumption may be mediated through mechanisms other than their effects on HDLC.


Metabolism-clinical and Experimental | 1987

The dyslipoproteinemia of anabolic steroid therapy: increase in hepatic triglyceride lipase precedes the decrease in high density lipoprotein2 cholesterol.

Deborah Applebaum-Bowden; Steven M. Haffner; William R. Hazzard

Administration of the androgenic anabolic steroid, stanozolol, is associated with decreased high density lipoprotein (HDL) cholesterol (primarily due to decreased HDL2 cholesterol) and increased levels of postheparin plasma hepatic triglyceride lipase (HTGL) activity. Since HTGL appears to play a role in HDL metabolism, we examined the temporal relationship between these changes. HDL cholesterol remained stable during the first two days of stanozolol administration, but decreased 14% (P less than .01) by the third day and 39% (P less than .01) by the seventh day of stanozolol. HDL2 cholesterol paralleled the total HDL cholesterol level and remained stable for the first two days, but decreased 22% (P less than .01) after three days and 71% (P less than .01) after seven days of stanozolol. In contrast, HTGL increased 62% (P less than .001) during the first day, 161% (P less than .001) with two days, 230% (P less than .001) with three days of stanozolol administration, and remained elevated thereafter. Thus, during stanozolol administration HTGL increased dramatically and clearly before any change in HDL or HDL2 cholesterol.


Metabolism-clinical and Experimental | 1984

Preliminary report: kinetic studies on the modulation of high-density lipoprotein, apolipoprotein, and subfraction metabolism by sex steroids in a postmenopausal woman.

William R. Hazzard; Steven M. Haffner; Rampratap S. Kushwaha; Deborah Applebaum-Bowden; David M. Foster

To investigate the effects of estrogens and androgens on the metabolism of high density lipoproteins (HDL) and low density lipoproteins (LDL), a normolipidemic postmenopausal woman was studied under the following conditions: (1) during supplementation with ethinyl estradiol (0.06 mg/d); (2) without sex steroid therapy; (3) during treatment with stanozolol, an androgenic, anabolic steroid (6 mg/d). During these manipulations HDL and LDL cholesterol levels fluctuated widely but reciprocally: during estrogen supplementation HDL increased while LDL decreased; during stanozolol HDL-C decreased while LDL-C increased. Simultaneous changes in post-heparin plasma hepatic triglyceride lipase activity paralleled those of LDL (and opposed those of HDL), decreasing with estrogen and increasing with stanozolol. During all three phases, autologous 125I-HDL turnover studies disclosed similarities between HDL2 and apolipoprotein A-I metabolism and between HDL3 and apolipoprotein A-II metabolism. In the untreated state the residence times of HDL2 and apo A-I were only half those of HDL3 and apo A-II. During estrogen treatment HDL2 and apo A-I, residence times were selectively prolonged, coming to resemble those of HDL3 and apo A-II, which remained unchanged. By contrast, during stanozolol treatment HDL3 and apo A-II residence times were selectively reduced, coming to resemble those of HDL2 and apo A-I, which remained unchanged. Apo A-I levels increased on estrogen and decreased on stanozolol, while apo A-II remained stable. Hence, estrogen increased HDL primarily by retarding the catabolism of the HDL2 subfraction rich in apo A-I, whereas stanozolol decreased HDL by accelerating the catabolism of HDL3, relatively rich in apo A-II.(ABSTRACT TRUNCATED AT 250 WORDS)


Diabetologia | 1984

Retarded chylomicron apolipoprotein-B catabolism in Type 2 (non-insulin-dependent) diabetic subjects with lipaemia

Steven M. Haffner; David M. Foster; Rampratap S. Kushwaha; William R. Hazzard

SummaryTo define the kinetics of chylomicron apolipoprotein-B catabolism in diabetic subjects with lipaemia, autologous chylomicrons (Sf 400) harvested from plasma following an oral fat load were radioiodinated and re-injected. The radioactivity in the tetramethylurea-insoluble, non-lipid Sf>400 lipoprotein fraction was followed in serial samples over 60–72h on a fat-free, isocaloric diet in: (1) five normal subjects; (2) four hypertriglyceridaemic, non-diabetic subjects; and (3) five diabetic patients (one subject, No. 3, was studied twice). The plasma apolipoprotein-B decay curve for the Sf 400 fraction disclosed biphasic disappearance: a rapid first phase (residence time 0.8–1.9 h) accounting for the large majority of removal (60%–95%) and a slower second phase (residence time 3.6–47.6 h), accounting for the remainder. Total chylomicron apolipoprotein-B residence times were similar in normolipidaemic (1.8–7.3 h) and hypertriglyceridaemic (2.3–10.3 h) non-diabetic subjects and the mildly hypertriglyceridaemic diabetic patients (5.6 and 5.8 h). In the untreated lipaemic diabetic subjects (Nos. 1 and 2), only a single, much slower phase was observed (total chylomicron apolipoprotein-B residence time 38.5–58 h). Adipose tissue biopsy in one of these subjects (No. 1) disclosed profoundly low lipoprotein lipase activity. The lipaemic diabetic subject (No. 3) studied early during treatment showed an intermediate pattern. These studies suggest a key role for insulin-dependent, lipoprotein lipase-mediated triglyceride hydrolysis in the removal of chylomicrons from plasma.


European Journal of Clinical Investigation | 1989

Metabolism of chylomicrons in subjects with dysbetalipoproteinaemia (type III hyperlipoproteinaemia)

Steven M. Haffner; R. S. Kushwaha; William R. Hazzard

Abstract. These studies were conducted to investigate whether subjects with dysbetalipoproteinaemia (type III hyperlipoproteinaemia) can catabolize chylomicrons normally and if chylomicron catabolism is related to the triglyceride pool size. Iodinated postprandial plasma chylomicrons were injected into subjects with dysbetalipoproteinaemia (n= 7), subjects with endogenous hypertriglyceridaemia (n=4), and normal subjects (n= 5). The subjects with dysbetalipoproteinaemia had VLDL‐cholesterol/total triglyceride ratios greater than 0.35 and were deficient in isoapoE‐3 and isoapoE‐4. The decay of radioactivity in chylomicron apoB was measured and residence times (RT) were calculated by measuring the area under the radioactivity decay curve. The mean RT for chylomicron apoB in subjects with dysbetalipoproteinaemia was 17.4 ± 3.5 h, which was significantly longer than in both subjects with endogenous hypertriglyceridaemia (4.8 ± 2.1 h) and also in normal subjects (5.9 ± 1.6 h). There was no significant correlation between chylomicron apoB RT and triglyceride levels in subjects with dysbetalipoproteinaemia or in other subjects. Thus, chylomicron apoB catabolism is retarded in subjects with dysbetalipoproteinaemia. The slow removal of chylomicron apoB in subjects with dysbetalipoproteinaemia does not seem to be attributable to an increased triglyceride pool size.


Metabolism-clinical and Experimental | 1984

Chylomicron and very low-density lipoprotein apolipoprotein B metabolism: Mechanism of the response to stanozolol in a patient with severe hypertriglyceridemia

William R. Hazzard; Rampratap S. Kushwaha; Deborah Applebaum-Bowden; Steven M. Haffner; Armin Steinmetz; David M. Foster

Studies of simultaneous autologous 131I-chylomicron (Sf greater than 400) and 125I-very low density lipoprotein (VLDL) (Sf 20 to 400) apolipoprotein B (apo B) were performed both before (triglyceride level c 1500 mg/dL) and during treatment with stanozolol, a 17 alpha-methyl anabolic androgenic steroid (triglyceride level c 750 mg/dL) in a 74-year-old woman with a past history of recurrent chylomicronemic pancreatitis. Both before and during stanozolol treatment chylomicron apo B disappeared rapidly and directly, little appearing in VLDL and virtually none in intermediate (IDL) or low density lipoproteins (LDL). Multicompartmental analysis indicated that the great majority of chylomicron apo B was removed via an extremely rapid compartment (estimated fractional catabolic rate [FCR], 5.0/h), accounting for 66% before and 88% during stanozolol treatment. The remaining 131I-apo B decayed biphasically, with total Sf greater than 400 residence times of 8.6 hours before and 3.7 hours during stanozolol treatment. Hence, despite a moderately depressed adipose tissue lipoprotein lipase activity, the subjects hypertriglyceridemia did not appear to proceed solely from retarded chylomicron removal, nor was the dramatic decrease in triglyceride in response to stanozolol a function only of the acceleration of such removal. VLDL apo B kinetics were analyzed by a multicompartmental model featuring a rapid, stepwise delipidation chain which proceeds either rapidly to IDL and LDL or to a slowly turning over compartment within VLDL. While VLDL. apo B synthesis remained essentially constant, the major effect of stanozolol was a substantial reduction in the fraction of VLDL apo B diverted to this slowly turning over compartment, which decreased from 5.0% before to 1.2% during treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

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John J. Albers

University of Washington

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