Effects of GHRP-2 and Cysteamine Administration on Growth Performance, Somatotropic Axis Hormone and Muscle Protein Deposition in Yaks (Bos grunniens) with Growth Retardation.

Hu R, Wang Z, Peng Q, Zou H, Wang H, Yu X, Jing X, Wang Y, Cao B, Bao S, Zhang W, Zhao S, Ji H, Kong X, Niu Q

PloS one19 Feb 2016Cited by 23 (Europe PMC)

PMID26894743PMCIDPMC4760683DOI10.1371/journal.pone.0149461PepBankPUB-26894743

Summary

UnlabelledThe objective of this study was to investigate the effects of growth hormone-releasing peptide-2 (GHRP-2) and cysteamine (CS) administration on growth performance in yaks with growth retardation and try to elucidate its regulatory mechanisms. Trial 1, thirty-six 1-year-old Qinghai high plateau yaks (body weight 38-83.2 kg) were randomly chosen for body weight and jugular blood samples collection. The relationship between body weight and serum GHRH (P < 0.05, R = 0.45), GH (P < 0.05, R = 0.47), IGF-1 (P < 0.05, R = 0.62) was significantly correlated in yaks colonies with lighter body weights. Trial 2, fifteen 1-year-old Qinghai high plateau yaks with growth retardation (average body weight 54.8 ± 8.24 kg) were randomly selected and assigned to negative control group (NG), GHRP-2 injection group (GG) and cysteamine feeding group (CG), with 5 yaks per group. Another five 1-year-old Qinghai high plateau yaks with normal growth performance (average body weight 75.3 ± 2.43 kg) were selected as positive control group (PG). The average daily gain (ADG) of the GG and CG were significantly higher than those in the PG and NG (P < 0.05). Both GHRP-2 and CS administration significantly enhanced the myofiber diameter and area of skeletal muscle (P<0.05). GHRP-2 significantly enhanced the serum GH and IGF-1 levels (P < 0.05), and up-regulated GHR, IGF-1 and IGF-1R mRNA expression in the liver and skeletal muscle (P < 0.05), enhanced the mRNA expression of PI3K, AKt and mTOR in the skeletal muscle (P<0.05). CS significantly reduced the serum SS levels and the hypothalamus SS mRNA expression (P < 0.05), and enhanced GHR and IGF-1 mRNA expression in the liver (P < 0.05), decreased the mRNA expression of muscle atrophy F-box (Atrogin-1) and muscle ring finger 1 (MuRF1) mRNA (P < 0.05).ConclusionsGrowth retardation in yaks was primarily due to somatotropic axis hormones secretion deficiency. Both GHRP-2 and CS administration can accelerate growth performance and GH, IGF-1 secretion in yaks with growth retardation. GHRP-2 enhanced muscle protein deposition mainly by up-regulated the protein synthesis pathways, whereas CS worked mainly by down-regulated the ubiquitin-proteasome pathway.

CC BYText from Europe PMC. Highlighted sentences are the source of results.

Results from this study6

6 results from studies that gave the peptide. No result from this study comes from people.

01AnimalAnimal study (in vivo)Efficacy outcome
In yaks with growth retardation, the GHRP‑2 injection group had higher average daily gain than the negative control and the normal-growth control group.
In plain wordsIn yaks with stunted growth, GHRP‑2 injection led to faster weight gain than in untreated yaks and in normal-growth yaks.
Peptide
GHRP-2
Outcome
IncreaseAverage daily gain
Study
yak (Bos grunniens)n = 5
1-year-old yaks with growth retardation
Comparator
Negative control and normal-growth positive control
Outcome group
Body weight · Metabolic and weight
Studied dose
Dose not stated · injectionAs given in this study (yak (Bos grunniens)).
Source sentences
Summary
The average daily gain (ADG) of the GG and CG were significantly higher than those in the PG and NG (P < 0.05)
1 context sentence(design, population, supporting numbers)
Summary · context
Trial 2, fifteen 1-year-old Qinghai high plateau yaks with growth retardation (average body weight 54.8 ± 8.24 kg) were randomly selected and assigned to negative control group (NG), GHRP-2 injection group (GG) and cysteamine feeding group (CG), with 5 yaks per group.
Show in the study text Report a problemFND-2689474301
02AnimalAnimal study (in vivo)Efficacy outcome
In yaks with growth retardation, GHRP‑2 administration increased the myofiber diameter and area of skeletal muscle.
In plain wordsIn yaks with stunted growth, GHRP‑2 made muscle fibres larger.
Peptide
GHRP-2
Outcome
IncreaseMyofiber diameter and area of skeletal muscle
Study
yak (Bos grunniens)n = 5
1-year-old yaks with growth retardation
Comparator
Negative control
Outcome group
Muscle injury and repair · Musculoskeletal
Studied dose
Dose not stated · injectionAs given in this study (yak (Bos grunniens)).
Source sentences
Summary
Both GHRP-2 and CS administration significantly enhanced the myofiber diameter and area of skeletal muscle (P<0.05).
1 context sentence(design, population, supporting numbers)
Summary · context
Trial 2, fifteen 1-year-old Qinghai high plateau yaks with growth retardation (average body weight 54.8 ± 8.24 kg) were randomly selected and assigned to negative control group (NG), GHRP-2 injection group (GG) and cysteamine feeding group (CG), with 5 yaks per group.
Show in the study text Report a problemFND-2689474302
03AnimalAnimal study (in vivo)Efficacy outcome
In yaks with growth retardation, GHRP‑2 increased serum GH levels.
In plain wordsIn yaks with stunted growth, GHRP‑2 raised blood growth hormone.
Peptide
GHRP-2
Outcome
IncreaseSerum GH
Study
yak (Bos grunniens)n = 5
1-year-old yaks with growth retardation
Comparator
Negative control
Outcome group
Growth hormone and IGF-1 · Endocrine and hormones
Studied dose
Dose not stated · injectionAs given in this study (yak (Bos grunniens)).
Source sentences
Summary
GHRP-2 significantly enhanced the serum GH and IGF-1 levels (P < 0.05)
1 context sentence(design, population, supporting numbers)
Summary · context
Trial 2, fifteen 1-year-old Qinghai high plateau yaks with growth retardation (average body weight 54.8 ± 8.24 kg) were randomly selected and assigned to negative control group (NG), GHRP-2 injection group (GG) and cysteamine feeding group (CG), with 5 yaks per group.
Show in the study text Report a problemFND-2689474303
04AnimalAnimal study (in vivo)Efficacy outcome
In yaks with growth retardation, GHRP‑2 increased serum IGF-1 levels.
In plain wordsIn yaks with stunted growth, GHRP‑2 raised blood IGF-1.
Peptide
GHRP-2
Outcome
IncreaseSerum IGF-1
Study
yak (Bos grunniens)n = 5
1-year-old yaks with growth retardation
Comparator
Negative control
Outcome group
Growth hormone and IGF-1 · Endocrine and hormones
Studied dose
Dose not stated · injectionAs given in this study (yak (Bos grunniens)).
Source sentences
Summary
GHRP-2 significantly enhanced the serum GH and IGF-1 levels (P < 0.05)
1 context sentence(design, population, supporting numbers)
Summary · context
Trial 2, fifteen 1-year-old Qinghai high plateau yaks with growth retardation (average body weight 54.8 ± 8.24 kg) were randomly selected and assigned to negative control group (NG), GHRP-2 injection group (GG) and cysteamine feeding group (CG), with 5 yaks per group.
Show in the study text Report a problemFND-2689474304
05AnimalAnimal study (in vivo)Efficacy outcome
In yaks with growth retardation, GHRP‑2 up-regulated GHR, IGF-1 and IGF-1R mRNA expression in the liver and skeletal muscle.
In plain wordsIn yaks with stunted growth, GHRP‑2 raised activity of growth-related genes in liver and muscle.
Peptide
GHRP-2
Outcome
IncreaseGHR, IGF-1 and IGF-1R mRNA in liver and skeletal muscle
Study
yak (Bos grunniens)n = 5
1-year-old yaks with growth retardation
Comparator
Negative control
Outcome group
Growth hormone and IGF-1 · Endocrine and hormones
Studied dose
Dose not stated · injectionAs given in this study (yak (Bos grunniens)).
Source sentences
Summary
up-regulated GHR, IGF-1 and IGF-1R mRNA expression in the liver and skeletal muscle (P < 0.05)
1 context sentence(design, population, supporting numbers)
Summary · context
Trial 2, fifteen 1-year-old Qinghai high plateau yaks with growth retardation (average body weight 54.8 ± 8.24 kg) were randomly selected and assigned to negative control group (NG), GHRP-2 injection group (GG) and cysteamine feeding group (CG), with 5 yaks per group.
Show in the study text Report a problemFND-2689474305
06AnimalAnimal study (in vivo)Efficacy outcome
In yaks with growth retardation, GHRP‑2 enhanced the mRNA expression of PI3K, AKt and mTOR in skeletal muscle.
In plain wordsIn yaks with stunted growth, GHRP‑2 raised activity of muscle protein-building genes.
Peptide
GHRP-2
Outcome
IncreasePI3K, AKt and mTOR mRNA in skeletal muscle
Study
yak (Bos grunniens)n = 5
1-year-old yaks with growth retardation
Comparator
Negative control
Outcome group
Muscle injury and repair · Musculoskeletal
Studied dose
Dose not stated · injectionAs given in this study (yak (Bos grunniens)).
Source sentences
Summary
enhanced the mRNA expression of PI3K, AKt and mTOR in the skeletal muscle (P<0.05)
1 context sentence(design, population, supporting numbers)
Summary · context
Trial 2, fifteen 1-year-old Qinghai high plateau yaks with growth retardation (average body weight 54.8 ± 8.24 kg) were randomly selected and assigned to negative control group (NG), GHRP-2 injection group (GG) and cysteamine feeding group (CG), with 5 yaks per group.
Show in the study text Report a problemFND-2689474306

AI wrote and checked these results. AI can make mistakes, so check important results against the source.

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Version 2Current
13 Oct 2026, 21:44 UTC
Study results updated
Version 1
13 Oct 2026, 16:31 UTC
First added · source update from Europe PMC

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