Analysis of insulin and insulin analogs from dried blood spots by means of liquid chromatography-high resolution mass spectrometry

9 Oct 2018

Analysis of insulin and insulin analogs from dried blood spots by means of liquid chromatography-high resolution mass spectrometry / Andreas Thomas, Mario Thevis. - (Drug Testing and Analysis 10 (2018) 11-12 Special Issue (November-December); p. 1761-1768)

  • PMID: 30298989
  • DOI: 10.1002/dta.2518


Abstract

While dried blood spot (DBS) analysis concerning low molecular mass molecules has become more and more established in various fields of analytical chemistry, the utility of DBS in determining peptides and proteins from DBS is yet comparably limited. In consideration of the fact that the apparent benefits of DBS sampling are similar for analytes of lower and higher molecular mass, dedicated (non-generic) sample preparation procedures are required that meet the needs for detecting peptidic drugs and hormones in DBS. The analysis of insulin and its synthetic analogs by mass spectrometry has received increased attention in several fields such as doping controls, forensics, and drug metabolism and pharmacokinetics studies. Hence, a strategy facilitating the analysis of insulin and its synthetic or animal analogs (human, Lispro, Aspart, Glulisine, Glargine, Detemir, Tresiba, and porcine and bovine insulin) from DBS was developed. The successful analysis of these substances at physiologically relevant concentrations was realized after ultrasonication-assisted extraction, immunoaffinity purification, and liquid chromatographic separation followed by high resolution mass spectrometric detection (with or without ion mobility). Assay validation demonstrated adequate sensitivity (LOD 0.5 ng/mL for most insulins), as well as precise (< 25%) and reproducible results for all included target insulins. Additionally, proof-of-principle data were obtained by the analysis of DBS samples obtained from healthy volunteers in non-fasting state as well as a sample from a diabetic volunteer treated with the fast acting analog insulin Aspart.

Quantification of insulin-like growth factor-1 in dried blood spots for detection of growth hormone abuse in sport

22 Dec 2012

Quantification of insulin-like growth factor-1 in dried blood spots for detection of growth hormone abuse in sport / Holly D. Cox, Jessica Rampton, Daniel Eichner. - (Analytical and Bioanalytical Chemistry 405 (2013) 6 (February); p. 1949-1958)

  • PMID: 23263515
  • DOI: 10.1007/s00216-012-6626-y


Abstract

There is significant evidence that athletes are using recombinant human growth hormone (rhGH) to enhance performance, and its use is banned by the World Anti-Doping Agency and professional sports leagues. Insulin-like growth factor-1 (IGF-1) is the primary mediator of growth hormone action and is used as a biomarker for the detection of rhGH abuse. The current biomarker-based method requires collection and expedited shipment of venous blood which is costly and may decrease the number of tests performed. Measurement of GH biomarkers in dried blood spots (DBS) would considerably simplify sample collection and shipping methods to allow testing of a greater number of samples regardless of location. A method was developed to quantify intact IGF-1 protein in DBS by liquid chromatography-tandem mass spectrometry. A step-wise acid-acetonitrile extraction was optimized to achieve a sensitive assay with a lower limit of quantification of 50 ng/mL. IGF-1 remained stable at room temperature for up to 8 days, which would allow shipment of DBS cards at ambient temperature. In a comparison between plasma concentrations of IGF-1 and concentrations measured from venous and finger prick DBS, there was good correlation and agreement, r(2) of 0.8551 and accuracy of 86-113 % for venous DBS and r(2) of 0.9586 and accuracy of 89-122 % for finger prick DBS. The method is intended for use as a rapid screening method for IGF-1 to be used in the biomarker method of rhGH abuse detection.

DHEA enhances effects of weight training on muscle mass and strength in elderly women and men

1 Nov 2006

DHEA enhances effects of weight training on muscle mass and strength in elderly women and men / Dennis T. Villareal, John O. Holloszy. - (American Journal of Physiology. Endocrinology and Metabolism 291 (2006) 5 (November); p. E1003-E1008)

  • PMID: 16787962
  • DOI: 10.1152/ajpendo.00100.2006


Abstract

The plasma levels of dehydroepiandrosterone (DHEA) and its sulfated form (DHEAS) decline approximately 80% between the ages of 25 and 75 yr. Muscle mass and strength also decrease with aging. Published data on the effects of DHEA replacement on muscle mass and strength are conflicting. The goals of this study were to determine whether DHEA replacement increases muscle mass and strength and/or enhances the effects of heavy resistance exercise in elderly women and men. We conducted a randomized, double-blind, placebo-controlled study of the effects of 10 mo of DHEA replacement therapy with the addition of weightlifting exercise training during the last 4 mo of the study (DHEA + exercise group, n = 29; placebo + exercise group, n = 27). DHEA alone for 6 mo did not significantly increase strength or thigh muscle volume. However, DHEA therapy potentiated the effect of 4 mo of weightlifting training on muscle strength, evaluated by means of one-repetition maximum measurement and Cybex dynamometry, and on thigh muscle volume, measured by magnetic resonance imaging. Serum insulin-like growth factor concentration increased in response to DHEA replacement. This study provides evidence that DHEA replacement has the beneficial effect of enhancing the increases in muscle mass and strength induced by heavy resistance exercise in elderly individuals.

A psychological comparison of females with anorexia nervosa and competitive male bodybuilders: body shape ideals in the extreme

15 Jan 2001

A psychological comparison of females with anorexia nervosa and competitive male bodybuilders : body shape ideals in the extreme /  Caroline Davis, Lori Scott-Robertson. - (Eating Behaviors 1 (2000) 1 (September); p. 33-46)

  • PMID: 15001065
  • DOI: 10.1016/s1471-0153(00)00007-6


Abstract

There is accumulating evidence that young men have become as concerned with their physical appearance as young women. However, different from women who want to achieve an ultra-slender body shape, most men want to increase their muscle mass and body size. Women with anorexia nervosa (AN) and competitive male bodybuilders are those who have taken the cultural standards of bodily perfection to the extreme, and both use unhealthy behaviours such as severe food restriction, excessive exercise, and steroids in pursuit of their goals. Findings of this study confirmed our prediction that the psychological profile of bodybuilders would be very similar to that found in women with AN. Both groups were significantly more obsessional, perfectionistic, anhedonic, and pathologically narcissistic than the general population. However, the bodybuilders reported very positive perceptions of their self-worth while the AN patients had very negative perceptions. Results are interpreted in the framework of a speculative developmental model of AN and bodybuilding, which focuses on the role of personality in the initiation and maintenance of excessive behaviours.

Dehydroepiandrosterone combined with exercise improves muscle strength and physical function in frail older women

2 Sep 2010

Dehydroepiandrosterone combined with exercise improves muscle strength and physical function in frail older women / Anne M Kenny, Rebecca S. Boxer, Alison Kleppinger, Jennifer Brindisi, Richard Feinn, Joseph A. Burleson. - (Journal of the American Geriatrics Society 58 (2010) 9 (September); p. 1707-1714)

  • PMID: 20863330
  • DOI: 10.1111/j.1532-5415.2010.03019.x


Abstract

Objectives: To investigate the effects of dehydroepiandrosterone (DHEA) combined with exercise on bone mass, strength, and physical function in older, frail women.

Design: Double-blind, randomized, placebo-controlled trial.

Setting: A major medical institution.

Participants: Ninety-nine women (mean age 76.6 ± 6.0) with low sulfated DHEA (DHEAS) levels, low bone mass, and frailty.

Intervention: Participants received 50 mg/d DHEA or placebo for 6 months; all received calcium and cholecalciferol. Women participated in 90-minute twice-weekly exercise regimens.

Measurements: Hormone levels, bone mineral density (BMD), bone turnover markers, body composition, upper and lower extremity strength, physical performance.

Results: Eighty-seven women (88%) completed 6 months. There were no significant changes in BMD or bone turnover markers. DHEA supplementation resulted in gains in lower extremity strength (from 459 ± 121 N to 484 ± 147 N; P=.01). There was also improvement in Short Physical Performance Battery score, a composite score that focuses on lower extremity function, in those taking DHEA (from 10.1 ± 1.8 to 10.7 ± 1.9; P=.02). There were significant changes in all hormone levels, including DHEAS, estradiol, estrone, and testosterone, and a decline in sex hormone-binding globulin levels in those taking DHEA.

Conclusion: DHEA supplementation improved lower extremity strength and function in older, frail women involved in a gentle exercise program of chair aerobics or yoga. No changes were found in BMD either due to small sample size, short duration of study or no effect. The physical function findings are promising and require further evaluation as frail women are at high risk for falls and fracture.

Effects of transdermal testosterone on bone and muscle in older men with low bioavailable testosterone levels, low bone mass, and physical frailty

1 Jun 2010

Effects of transdermal testosterone on bone and muscle in older men with low bioavailable testosterone levels, low bone mass, and physical frailty / Anne M. Kenny, Alison Kleppinger, Kristen Annis, Margaret Rathier, Bruce Browner, James O. Judge, Daniel McGee. - (Journal of the American Geriatrics Society 58 (2010) 6 (June); p. 1134-1143)

  • PMID: 20722847
  • PMCID: PMC3014265
  • DOI: 10.1111/j.1532-5415.2010.02865.x


Abstract

Objectives: To investigate the effects of testosterone supplementation on bone, body composition, muscle, physical function, and safety in older men.

Design: Double-blind, randomized, placebo-controlled trial.

Setting: A major medical institution.

Participants: One hundred thirty-one men (mean age 77.1 +/- 7.6) with low testosterone, history of fracture, or bone mineral density (BMD) T-score less than -2.0 and frailty.

Intervention: Participants received 5 mg/d of testosterone or placebo for 12 to 24 months; all received calcium (1500 mg/d diet and supplement) and cholecalciferol (1,000 IU/d).

Measurements: BMD of hip, lumbar spine, and mid-radius; body composition; sex hormones, calcium-regulating hormones; bone turnover markers; strength; physical performance; and safety parameters.

Results: Ninety-nine men (75.6%) completed 12 months, and 62 (47.3%) completed end therapy (mean 23 months; range 16-24 months for 62 who completed therapy). Study adherence was 54%, with 40% of subjects maintaining 70% or greater adherence. Testosterone and bioavailable testosterone levels at 12 months were 583 ng/dL and 157 ng/dL, respectively, in the treatment group. BMD on testosterone increased 1.4% at the femoral neck and 3.2% at the lumbar spine (P=.005) and decreased 1.3% at the mid-radius (P<.001). There was an increase in lean mass and a decrease in fat mass in the testosterone group but no differences in strength or physical performance. There were no differences in safety parameters.

Conclusion: Older, frail men receiving testosterone replacement increased testosterone levels and had favorable changes in body composition, modest changes in axial BMD, and no substantial changes in physical function.

Effects of DHEA replacement on bone mineral density and body composition in elderly women and men

9 Oct 2008

Effects of DHEA replacement on bone mineral density and body composition in elderly women and men / Dennis T. Villareal, John O. Holloszy, Wendy M. Kohrt. - (Clinical Endocrnology 53 (2000) 5 (November); p. 561-568)

  • PMID: 11106916
  • DOI: 10.1046/j.1365-2265.2000.01131.x


Abstract

Objective: Dehydroepiandrosterone (DHEA) is a precursor for both oestrogens and androgens. Its marked decline with ageing may influence age-related changes in tissues influenced by sex hormones. The aim of this study was to determine the effects of DHEA replacement on bone mineral density (BMD) and body composition in elderly women and men with low serum DHEA sulphate (DHEAS) levels.

Design: Prospective 6 month trial of oral DHEA replacement, 50 mg/day.

Patients: Experimental subjects were 10 women and eight men, aged 73 +/- 1 years. Control subjects were 10 women and eight men, aged 74 +/- 1 years.

Measurements: BMD, body composition, serum markers of bone turnover, serum lipids and lipoproteins, oral glucose tolerance, serum IGF-I, total serum oestrogens and testosterone.

Results: BMD of the total body and lumbar spine increased (mean +/- SEM; 1.6 +/- 0.6% and 2.5 +/- 0.8%, respectively; both P < or = 0.05), fat mass decreased (- 1.3 +/- 0.4 kg; P < 0.01) and fat-free mass increased (0.9 +/- 0.4 kg; P < or = 0. 05) in response to DHEA replacement. DHEA replacement also resulted in increases in serum IGF-I (from 108 +/- 8 to 143 +/- 7 microg/l; P < 0.01) and total serum testosterone concentrations (from 10.7 +/- 1.2 to 15.6 +/- 1.8 nmol/l in the men and from 2.1 +/- 0.2 to 4.5 +/- 0.4 nmol/l in the women; both P < or = 0.05).

Conclusions: The results provide preliminary evidence that DHEA replacement in those elderly women and men who have very low serum DHEAS levels can partially reverse age-related changes in fat mass, fat-free mass, and BMD, and raise the possibility that increases in IGF-I and/or testosterone play a role in mediating these effects of DHEA.

Doping as a Manifestation of a Narcissistic Civilization

4 Jul 2019

Doping as a Manifestation of a Narcissistic Civilization
Konstantinos Dedousis. - (Sport, Ethics and Philosophy (2019) 4 July; p. 1-15)

  • DOI: 10.1080/17511321.2019.1638960


Abstract

Over every and each sport event, a dark veil spreads and obfuscates the celebration: doping. Although anti-doping policies have been widely applied, controlling and diminishing this phenomenon has not been achieved yet and the use of doping is commonplace. In this article, I propose the concept of narcissistic civilization as a tool to interpret this phenomenon. I seek for a parallel reading between the Freudian idea of narcissism and its extension to social narcissism by Fromm, together with Heidegger’s analysis of technology, keeping in mind that doping is a technological application. In this way I point out that both theories share a common view in that humans tend to fail in the distinction between the external reality as an object and their own self as the interpreter, that is between the ¨I¨ and the ¨not I¨. By making this fusion of the two theories that originate from different intellectual traditions, I aspire to provide an interpretation tool for the broad use of doping: I conclude that doping can be understood with the assumption of a narcissistic civilization, focused on technology, that calls for the use of PEDs.

Effect of growth hormone and resistance exercise on muscle growth and strength in older men

1 Feb 1995

Effect of growth hormone and resistance exercise on muscle growth and strength in older men / Kevin E. Yaraheski, Jeffrey J. Zachwieja, Jill A. Campbell, Dennis M. Bier. - (American journal of physiology. Endocrinology and metabolism 268 (1995) 2 (February); E268-E276)

  • PMID: 7864103
  • DOI: 10.1152/ajpendo.1995.268.2.E268


Abstract

The purpose of this study was to determine whether growth hormone (GH) administration enhances the muscle protein anabolism associated with heavy-resistance exercise training in older men. Twenty-three healthy, sedentary men (67 +/- 1 yr) with low serum insulin-like growth factor I levels followed a 16-wk progressive resistance exercise program (75-90% max strength, 4 days/wk) after random assignment to either a GH (12.5-24 micrograms.kg-1.day-1; n = 8) or placebo (n = 15) group. Fat-free mass (FFM) and total body water increased more in the GH group. Whole body protein synthesis and breakdown rates increased in the GH group after treatment. However, increments in vastus lateralis muscle protein synthesis rate, urinary creatinine excretion, and training-specific isotonic and isokinetic muscle strength were similar in both groups, while 24-h urinary 3-methylhistidine excretion was unchanged after treatment. These observations suggest that resistance exercise training improved muscle strength and anabolism in older men, but these improvements were not enhanced when exercise was combined with daily GH administration. The greater increase in FFM with GH treatment may have been due to an increase in noncontractile protein and fluid retention.

Short-term growth hormone treatment does not increase muscle protein synthesis in experienced weight lifters

1 Jun 1993

Short-term growth hormone treatment does not increase muscle protein synthesis in experienced weight lifters / Kevin E. Yaraheski, Jeffrey J. Zachwieja, Theodore J. Angelopoulos, Dennis M. Bier. - (Journal of Applied Physiology 74 (1993) 6 (June); p. 3073-3076)

  • PMID: 8366011
  • DOI: 10.1152/jappl.1993.74.6.3073


Abstract

The purpose of this study was to determine whether recombinant human growth hormone (GH) administration enhances muscle protein anabolism in experienced weight lifters. The fractional rate of skeletal muscle protein synthesis and the whole body rate of protein breakdown were determined during a constant intravenous infusion of [13C]leucine in 7 young (23 +/- 2 yr; 86.2 +/- 4.6 kg) healthy experienced male weight lifters before and at the end of 14 days of subcutaneous GH administration (40 microgram.kg-1 x day-1). GH administration increased fasting serum insulin-like growth factor-I (from 224 +/- 20 to 589 +/- 80 ng/ml, P = 0.002) but did not increase the fractional rate of muscle protein synthesis (from 0.034 +/- 0.004 to 0.034 +/- 0.002%/h) or reduce the rate of whole body protein breakdown (from 103 +/- 4 to 108 +/- 5 mumol.kg-1 x h-1). These findings suggest that short-term GH treatment does not increase the rate of muscle protein synthesis or reduce the rate of whole body protein breakdown, metabolic alterations that would promote muscle protein anabolism in experienced weight lifters attempting to further increase muscle mass.

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