Influence of short- and long-term treadmill exercises on levels of ghrelin, obestatin and NPY in plasma and brain extraction of obese rats

This study aims to clarify the effects of exercise on levels of appetite regulatory hormones in plasma and hypothalamus of obese rats. Diet-induced obese rats undergo short- (40 min) and long-term (40 min, 5 days/week for 8 weeks) exercises. The rats ran at a speed of 20 m/min on a 5° slope treadmill. Rats undergoing short-term exercise were divided into C, E0, E1, E3, E12, and E24. Rats undergoing long-term exercise (LE) were compared to long-term control (LC). Concentrations of ghrelin, obestatin, and neuropeptide Y (NPY) were measured using radio immuno-assay. Expression of ghrelin receptor (GHSR-1a), putative obestatin receptor (GPR-39), and NPY in the hypothalamus was measured by quantitative RT-PCR. After short-term exercise, the plasma concentrations of ghrelin and obestatin were not changed, but NPY decreased. Ghrelin and obestatin in the hypothalamus decreased, and recovered 12 until 24 h. NPY increased and recovered after 24 h. Expression of GHSR-1a and NPY was not changed and GPR-39 was not observed. In LE, these changes are different in plasma and hypothalamus. It would be concluded appetite and body weight of obese rats are decreased by exercise through reduced level of ghrelin in the hypothalamus. Obestatin seems to have no effect in exercise-induced change in appetite.     

肥胖大鼠形成过程中血清瘦素、血浆Ghrelin及下丘脑神经肽Y水平的变化

目的 观察在食源性肥胖（DIO）大鼠模型形成过程中,血清瘦素（Leptin）、血浆Ghrelin及下丘脑神经肽Y（NPY）的变化. 方法 取模型形成过程中2个时间点,分为正常对照（NC）组、DIO4周组（高脂饮食喂养4周）和DIO 8周组（高脂饮食喂养8周）.测量血清Leptin、血浆Ghrelin水平及下丘脑NPY浓度和mRNA的表达. 结果 在DIO大鼠模型形成过程中,DIO 4周和DIO 8周组空腹血清Leptin浓度明显高于NC组[（0.34±0.05）,（0.49±0.03） vs （0.24±0.03） ng/ml]（P＜0.05）;空腹血浆Ghrelin浓度明显低于NC组[（1.84±0.21）,（1.62±0.23） vs （2.01±0.20） ng/ml]（P＜0.05）;下丘脑NPY浓度及mRNA表达均明显高于NC组[NPY浓度：（162.8±20.1）,（196.2±19.9）vs（134.3±17.2）pg/ml;NPY mRNA：（1.16±0.13）,（1.55±0.16）vs（0.87±0.16）]（P均＜0.05）.下丘脑NPY浓度及mRNA表达与血清Leptin浓度呈正相关（r分别为0.950、0.914,P＜0.05）,与血浆Ghrelin浓度呈负相关（r分别为-0.889、-0.908,P＜0.05）. 结论 随着DIO大鼠肥胖动物模型的形成,下丘脑NPY表达逐渐增强,与空腹血清Leptin浓度正相关,与空腹血浆Ghrelin浓度负相关.     

复方阿嗪米特联合多酶片治疗功能性消化不良的效果观察

目的 研究复方阿嗪米特肠溶片联合多酶片治疗功能性消化不良的效果。方法 选择2016年1月—2018年12月泰州市第三人民医院收治的60例功能性消化不良患者,随机分为两组,每组各30例。对照组患者口服多酶片,3片/次,3次/d。观察组在对照组的基础上加服复方阿嗪米特肠溶片,10 mg/次,3次/d。两组患者均治疗1个月。比较两组的临床治疗效果,症状改善情况和胃肠激素水平。结果 治疗后,观察组的有效率为93.33%,明显高于对照组的70.00%（P<0.05）。治疗后,两组餐后饱胀、嗳气、上腹痛以及上腹部烧灼感评分均明显降低（P<0.05）,且观察组症状评分明显更低（P<0.05）。治疗后,两组的胃动素（MTL）和神经肽Y（NPY）水平明显升高,血管活性肽（VIP）水平均明显降低（P<0.05）,且观察组胃肠激素水平明显优于对照组（P<0.05）。两组腹胀、腹泻、呕吐和头晕的发生率无明显的差异（P>0.05）。结论 复方阿嗪米特肠溶片联合多酶片能更为显著地改善功能性消化不良的症状,提高疗效,调节胃肠激素水平。     

The role of hypothalamic estrogen receptors in metabolic regulation

Estrogens regulate key features of metabolism, including food intake, body weight, energy expenditure, insulin sensitivity, leptin sensitivity, and body fat distribution. There are two ‘classical’ estrogen receptors (ERs): estrogen receptor alpha (ERS1) and estrogen receptor beta (ERS2). Human and murine data indicate ERS1 contributes to metabolic regulation more so than ESR2. For example, there are human inactivating mutations of ERS1 which recapitulate aspects of the metabolic syndrome in both men and women. Much of our understanding of the metabolic roles of ERS1 was initially uncovered in estrogen receptor α-null mice (ERS1^−/−); these mice display aspects of the metabolic syndrome, including increased body weight, increased visceral fat deposition and dysregulated glucose intolerance. Recent data further implicate ERS1 in specific tissues and neuronal populations as being critical for regulating food intake, energy expenditure, body fat distribution and adipose tissue function. This review will focus predominantly on the role of hypothalamic ERs and their critical role in regulating all aspects of energy homeostasis and metabolism.     

Des-acyl ghrelin exhibits pro-anabolic and anti-catabolic effects on C2C12 myotubes exposed to cytokines and reduces burn-induced muscle proteolysis in rats

Although ghrelin and GHRP-2 have been shown to inhibit skeletal muscle proteolysis in rats with burn injury, the effects of des-acyl ghrelin (DAG) have not been reported. In this paper, we demonstrate that continuous 24h administration of DAG attenuated burn-induced EDL muscle proteolysis, and normalized elevated TNFα mRNA. Combined treatment of cultured C2C12 myotubes with TNFα and IFN-γ (TNF+IFN) inhibited protein synthesis and increased protein breakdown; DAG abolished both effects. PI3 kinase inhibition by LY294002 and mTOR inhibition by rapamycin blocked the reversal of the anti-anabolic effects of TNF+IFN-treated myotubes by DAG. DAG also reversed or attenuated the TNF+IFN-induced reduction in phosphorylation of Akt, FOXO1, 4E-BP-1, and GSK-3β in myotubes. Furthermore, DAG attenuated the atrophy signal, phospho-NF-κB, and the mRNA expression of MAFbx and MuRF1, upregulated by TNF+IFN in C2C12 myotubes. We conclude that DAG reduces muscle cachexia produced by injury and proinflammatory cytokines, and that DAG or DAG-based compounds may be useful in treating wasting disorders.     

Neuropeptides and hippocampal neurogenesis

Hippocampal neurogenesis is important for modulating the behavioural responses to stress and for certain forms of learning and memory. The mechanisms underlying the necessary coupling of neuronal activity to neural stem/progenitor cell (NSPC) function remain poorly understood. Within the dentate subgranular stem cell niche, local interneurons appear to play an important part in this excitation-neurogenesis coupling via GABAergic transmission, which promotes neuronal differentiation and integration.     

Excessive release of endogenous neuropeptide Y into cerebrospinal fluid after treatment of spontaneous subarachnoid haemorrhage and its possible impact on self-reported neuropsychological performance – results of a prospective clinical pilot study on good-grade patients

ABSTRACT

Objectives: Neuropsychological dysfunction after treatment of spontaneous subarachnoid haemorrhage (sSAH) is common but underreported. The vasoconstrictor neuropeptide Y (NPY) is excessively released after sSAH and in psychiatric disorders. We prospectively analysed the treatment-specific differences in the secretion of endogenous cerebrospinal fluid (CSF) NPY during the acute stage after sSAH and its impact on cognitive processing.

Methods: A total of 26 consecutive patients (f:m = 13:8; mean age 50.6 years) with good-grade sSAH were enrolled (drop out n = 5): n = 9 underwent endovascular aneurysm occlusion, n = 6 microsurgery, and n = 6 patients with perimesencephalic SAH received standardized intensive medical care. Ventricular CSF was drawn daily from day 1–10. CSF NPY levels were determined with competitive enzyme immunoassay. All patients underwent neuropsychological self-report assessment [36-Item Short Form Health Survey (SF-36) and ICD-10-Symptom-Rating questionnaire (ISR)] after the onset of sSAH (day 11–35; t₁) and at the 6-month follow-up (t₂).

Results: At t₁, increased mean levels of NPY in CSF significantly correlated with impaired performance in most ISR scores (ISR total p = .018, depression p = .035, anxiety p = .008, nutrition disorder p = .047, supplementary items p = .038) and in several psychological SF-36 items (vitality p = .019, general mental health p = .001, mental component summary p = .025).

Discussion: To the best of our knowledge, this study is the first to correlate the levels of endogenous NPY in supratentorial CSF with cognitive outcome in good-grade sSAH patients. Excessive NPY release into CSF may have a short-term influence on the pathogenesis of neuropsychological deficits. The impact of cerebrovascular manipulation on NPY release has to be further elucidated.

Abbreviations: ANOVA: analysis of variance; aSAH: aneurysmal subarachnoid haemorrhage; AUC: area under the curve; CBF: cerebral blood flow; CSF: cerebrospinal fluid; CT (scan): computed tomography (scan); CV: cerebral vasospasm; DIND: delayed ischemic neurological deficit; DSA: digital subtraction angiography; EIA: enzyme immunoassay; EV: endovascular aneurysm occlusion; EVD: external ventricular drainage; FU: 6-month follow-up; GCS: Glasgow Coma Scale; Ghp: general health perceptions; GOS: Glasgow Outcome Scale; h: hour/s; HH: Hunt and Hess; ICU: intensive care unit; ISR: ICD-10-Symptom-Rating questionnaire; MCS: mental component summary; Mhi: general mental health; min: minute/s; min-max: minimum – maximum; ml: millilitre; mRS: modified Ranking Scale; MS: microsurgical clipping, microsurgical aneurysm occlusion; ng: nanograms; no. [n]: number; NPY: Neuropeptide Y; p: p value; Pain: bodily pain; PCS: physical component summary; Pfi: physical functioning; pSAH: perimesencephalic subarachnoid haemorrhage; PTSD: posttraumatic stress disorder; QoL: quality of life; Rawhtran: health transition item; Rolem: role limitations because of emotional problems; Rolph: role limitations due to physical health problems; SAH: subarachnoid haemorrhage; SD: standard deviation; SF-36: 36-Item Short Form Health Survey; Social: social functioning; sSAH: spontaneous subarachnoid haemorrhage; TCD: trans-cranial Doppler ultrasound; (test) t₁: test in the sub-acute phase after the onset of bleeding (between day 11 and 35 after subarachnoid haemorrhage); (test) t₂: test in the short-term (chronic phase) after treatment at 6-month follow-up; test t₁ - t₂: intergroup development from t₁ to t₂; Vital: vitality; vs: versus.     

Sympathectomy decreases size and invasiveness of tongue cancer in rats

The sympathetic nervous system plays a role in carcinogenesis wherein locally released sympathetic neurotransmitters affect proliferation, angiogenesis, vessel permeability, lymphocyte traffic and cytokine production. The present in vivo study was designed to investigate whether surgical sympathectomy, both unilateral and bilateral, had an effect on tumor growth, interstitial fluid pressure (IFP) and lymphatics in rat tongue cancer. We used 4-nitroquinoline-1-oxide (4-NQO) in drinking water for 19 weeks to induce tongue cancer in 20 Dark Agouti rats. After 11 weeks, one group underwent unilateral sympathectomy and another underwent bilateral sympathectomy, while the third group underwent sham surgery. By 19 weeks, tumors in the bilaterally sympathectomized (BL-SCGx) rats were significantly smaller (P<0.05), more diffuse in appearance and less invasive (P<0.05) compared with the large exophytic tumors in the sham-operated rats. The relative lymphatic area was significantly decreased (P<0.05) in tumors in the BL-SCGx rats compared with the sham group. Interestingly, the tumors in rats that underwent unilateral or bilateral sympathectomy had a significantly lower (P<0.05) IFP than those in sham rats. Lack of tyrosine hydroxylase (TH) immunoreactive nerves and few neuropeptide Y (NPY) positive fibers indicate absence of sympathetic nerve fibers in the bilateral sympathectomized group. The peritumoral lymph vessel area was correlated with the tumor size (P<0.001), depth of invasion (P<0.001), weight of rats (P<0.005) and IFP (P<0.05). In conclusion, the present study presents evidence that deprivation of sympathetic nerves decreases tumor growth in rat tongue, probably caused by decreasing IFP and lymph vessel area.     

重复经颅磁刺激联合盐酸帕罗西汀对卒中后抑郁症患者治疗效果观察

目的 探讨重复经颅磁刺激(rTMS)联合盐酸帕罗西汀对卒中后抑郁症(PSD)患者HAMD评分及血清神经肽Y(NPY)、促肾上腺皮质激素释放因子(CRF)、脑源性神经营养因子(BDNF)水平变化的影响。 方法 选取郑州大学第二附属医院2014年11月至2017年2月PSD患者68例,随机数字表法分组,各34例。对照组采用盐酸帕罗西汀,观察组采用盐酸帕罗西汀+rTMS,两组均持续治疗2个月。入院时及治疗结束后统计对比两组抑郁评分(HAMD、MARDS、SDS)、血清NPY、BDNF、CRF水平、临床疗效及不良反应发生率。 结果 ①两组治疗后MARDS、HAMD及SDS分值低于治疗前,且观察组较对照组低(P＜0.05);②两组治疗有效率比较,观察组94.12%(32/34)较对照组64.71%(22/34)高(P＜0.05);③两组治疗后血清CRF水平低于治疗前,BDNF及NPY水平高于治疗前,且观察组各指标优于对照组(P＜0.05);④两组不良反应发生率比较,观察组14.71%(5/34)与对照组8.82%(3/34)间差异无统计学意义(P＞0.05)。 结论 联合采用盐酸帕罗西汀及rTMS治疗卒中后抑郁症效果显著,可有效改善血清NPY、BDNF、CRF水平,降低HAMD评分,减轻患者抑郁程度,提高治疗效果,且不会增加不良反应发生风险,具有安全性。     

Involvement of hypothalamic PI3K–STAT3 signalling in regulating appetite suppression mediated by amphetamine

BACKGROUND AND PURPOSE

Appetite suppression induced by amphetamine has been attributed to its inhibition of neuropeptide Y (NPY) neurons and activation of pro-opiomelanocortin (POMC) neurons in the hypothalamus. This study examined whether STAT3 was involved in these actions of amphetamine.

EXPERIMENTAL APPROACH

Rats were given amphetamine daily for 4 days. Changes in the expression of NPY, POMC, melanocortin MC₃ receptors, PI3K and STAT3 in the hypothalamus were assessed by RT-PCR and Western blotting. Antisense oligonucleotides to STAT3 were also used.

KEY RESULTS

Expression of NPY decreased with a maximum effect day 2 of amphetamine treatment. Expression of POMC, MC₃ receptors, PI3K and STAT3 increased with a maximum response on day 2. Moreover, phosphorylation of STAT3 and its DNA binding activity increased and was expressed in a similar pattern. Infusion (i.c.v.) of STAT3 antisense at 60 min before amphetamine treatment, partly blocked amphetamine-induced anorexia and modulated expression of NPY, POMC, MC₃ receptors and PI3K, indicating the involvement of STAT3 in amphetamine-treated rats.

CONCLUSIONS AND IMPLICATIONS

Hypothalamic PI3K–STAT3 signalling participated in the regulation of NPY- and POMC-mediated appetite suppression. These findings may contribute to a better understanding of anorectic drugs.