This is a working overview of 内脏脂肪, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2025-12-13 and is reviewed periodically as new material appears.
Tesamorelin is a synthetic peptide analog of growth hormone-releasing hormone, built from 44 amino acids. Its sequence follows the natural human GHRH(1-44) backbone, with a trans-3-hexenoyl group attached to the N-terminal tyrosine. This modification blocks recognition by dipeptidyl peptidase IV, the enzyme that rapidly truncates the native hormone in circulation. The result is a molecule with a substantially longer plasma residence time than unmodified GHRH, which makes it practical for clinical and laboratory study.
Receptor-level activity begins when the peptide binds the GHRH receptor, a class B G-protein-coupled receptor found on pituitary somatotroph cells. Occupancy triggers Gs-mediated activation of adenylyl cyclase and a rise in intracellular cyclic AMP, which in turn promotes synthesis and pulsatile release of growth hormone. Because the compound acts upstream of the growth hormone axis rather than supplying hormone directly, its effect depends on intact pituitary function. Binding studies in cell culture and animal models have established this pathway; the detailed kinetics of receptor recycling in humans remain less well characterized.
tesamorelin 是一种人工合成的四十四肽，序列与内源性生长激素释放激素（GHRH）的 1-44 片段一致，区别在于 N 端加接了一个反式-3-己烯酰基。该修饰抑制二肽基肽酶 IV 的快速切割，从而延长分子在循环中的存留时间。作为肽类分子，它难以经胃肠道吸收，文献中讨论的均是注射途径。分类上通常把它归为 GHRH 类似物，以区别于生长激素本身。
作用位置在垂体前叶。tesamorelin 与 GHRH 受体结合后激活腺苷酸环化酶，升高细胞内 cAMP，再经蛋白激酶 A 通路促进生长激素的合成与释放。由于它作用于内源调控节点，生长激素仍以脉冲方式分泌，而不是被持续抬升到固定水平。生长激素随后在肝脏等组织诱导胰岛素样生长因子 1 产生，构成完整的生长激素轴响应。
| Property | Value | Notes |
|---|---|---|
| Molecular class | Synthetic peptide | GHRH receptor agonist |
| Residue count | 44 amino acids | Matches human GHRH(1-44) length |
| N-terminal modification | trans-3-hexenoyl group | Confers resistance to dipeptidyl peptidase IV |
| Appearance | White to off-white powder | Typically supplied lyophilized in a sealed vial |
| Solubility class | Freely soluble in water | Hydrophilic peptide; polar solvent compatible |
Tesamorelin is a synthetic peptide analog of growth hormone-releasing hormone (GHRH). Its sequence corresponds to the 44-amino-acid form of human GHRH with a trans-3-hexenoyl group attached to the N-terminal tyrosine. This modification slows enzymatic cleavage and extends the peptide's activity relative to the native hormone. The compound is produced by solid-phase peptide synthesis and supplied as a lyophilized powder. Researchers classify it as a GHRH receptor agonist. Its structure places it in the same family as other growth hormone secretagogues that act on the pituitary.
Binding of tesamorelin to GHRH receptors on pituitary somatotroph cells triggers cyclic AMP signaling and the release of growth hormone into circulation. Because the peptide acts upstream of the growth hormone axis, its effects are partly mediated by hepatic insulin-like growth factor 1 (IGF-1) production. The pulsatile character of endogenous growth hormone secretion is preserved rather than replaced. Whether amplified signaling produces effects beyond those of native GHRH remains an area of ongoing investigation.
Clinical interest in tesamorelin arose from the need to address visceral adiposity in people living with HIV. Antiretroviral therapy improved survival but was associated in some patients with central fat accumulation, altered lipid profiles, and metabolic complications. This condition, often called HIV-associated lipodystrophy, involves excess visceral adipose tissue that is difficult to manage through diet and exercise alone. Investigators evaluated tesamorelin because GHRH analogs can stimulate growth hormone secretion and influence fat distribution without direct liposuction or invasive procedures.
A Phase 3 program led to regulatory approval in the United States in 2010 for reduction of excess visceral abdominal fat in adults with HIV and lipodystrophy. Subsequent studies examined effects on liver fat, muscle area, and metabolic markers, with mixed findings for some endpoints. Long-term cardiovascular outcomes and effects on mortality remain uncertain because most trials were relatively short and focused on imaging-based fat measurements. Use in populations without HIV has been studied experimentally but is not part of the approved indication.
The Algiers Accords, officially referred to as the Accord for Peace and Reconciliation in Mali, is a 2015 agreement to end the Mali War. The agreement was signed on May 15 and June 20, 2015, in Bamako, following negotiations in Algiers between the Republic of Mali and Coordination of Azawad Movements (CMA). The agreement was eventually terminated by the Malian government on January 25, 2024, amid open conflict with the CMA that sprung from the withdrawal of MINUSMA peacekeepers and presence of Wagner Group forces.
Hypothyroidism when untreated may lead to infertility and an increased risk of miscarriage or infant death around the time of birth, mostly in severe cases of hypothyroidism. Women are affected by hypothyroidism in 0.3–0.5% of pregnancies. Subclinical hypothyroidism during pregnancy is associated with birth of the baby before 37 weeks of pregnancy.
=== Long-term effects === Most of the research studies on the effects of the low-FODMAP diet are short-term, usually lasting about 28 days. When the diet is suddenly changed, the gut microbiota may undergo rapid changes in the short term. The long term stability of the changes in microbiota caused by the low-FODMAP diet and its effects on health are unclear. It is not known if the changes in microbiota are irreversible. Long-term use of low-FODMAP diet may have negative effects because it causes a detrimental impact on the gut microbiota and metabolome. It should only be used for short periods of time and under the advice of a specialist. The true impact of this diet on health is not fully understood. The restriction phase should not last for more than six weeks. A low-FODMAP diet is highly restrictive in various groups of nutrients, can be impractical to follow in the long term, and may add an unnecessary financial burden.
Sources: en.wikipedia.org
External (interface) pressure applied over an area of the body, especially over the bony prominences can result in obstruction of the blood capillaries, which deprives tissues of oxygen and nutrients, causing ischemia (deficiency of blood in a particular area), hypoxia (inadequate amount of oxygen available to the cells), edema, inflammation, and, finally, necrosis and ulcer formation. Ulcers due to external pressure occur over the sacrum and coccyx, followed by the trochanter and the calcaneus (heel). In healthy individuals, ulcers caused by external pressure do not occur when the body is stationary, such as during sleep, as involuntary movements of the body frequently occur, allowing for repositioning and the relief of pressure. Friction is damaging to the superficial blood vessels directly under the skin. It occurs when two surfaces rub against each other. The skin over the elbows can be injured due to friction. The back can also be injured when patients are pulled or slid over bed sheets while being moved up in bed or transferred onto a stretcher. Shearing is a separation of the skin from underlying tissues. When a patient is partially sitting up in bed, skin may stick to the sheet, making the skin susceptible to shearing in case underlying tissues move downward with the body toward the foot of the bed. This may also be possible on a patient who slides down while sitting in a chair. Moisture is also a common pressure ulcer culprit. Sweat, urine, feces, or excessive wound drainage can further exacerbate the damage done by pressure, friction, and shear.
Considering all decay modes, various models indicate a shift of the center of the island (i.e., the longest-living nuclide) from 298Fl to a lower atomic number, and competition between alpha decay and spontaneous fission in these nuclides; these include 100-year half-lives for 291Cn and 293Cn, a 1000-year half-life for 296Cn, a 300-year half-life for 294Ds, and a 3500-year half-life for 293Ds, with 294Ds and 296Cn exactly at the N = 184 shell closure. It has also been posited that this region of enhanced stability for elements with 112 ≤ Z ≤ 118 may instead be a consequence of nuclear deformation, and that the true center of the island of stability for spherical superheavy nuclei lies around 306Ubb (Z = 122, N = 184). This model defines the island of stability as the region with the greatest resistance to fission rather than the longest total half-lives; the nuclide 306Ubb is still predicted to have a short half-life with respect to alpha decay. The island of stability for spherical nuclei may also be a "coral reef" (i.e., a broad region of increased stability without a clear "peak") around N = 184 and 114 ≤ Z ≤ 120, with half-lives rapidly decreasing at higher atomic number, due to combined effects from proton and neutron shell closures. Another potentially significant decay mode for the heaviest superheavy elements was proposed to be cluster decay by Romanian physicists Dorin N. Poenaru and Radu A. Gherghescu and German physicist Walter Greiner.
ACS Applied Materials & Interfaces. 16 (12): 14633–14644. Bibcode:2024AAMI...1614633K. doi:10.1021/acsami.4c02243. PMC 10982941. PMID 38483312. Karki, Sandeep; Malhotra, Sahil; Ijaz, Muhammad; Rollet, Nicolas; O'Cearbhaill, Eoin D.; Bini, Estela; Brayden, David J. (2026). "A pullulan-based bilayer film for buccal delivery of a GLP-1 peptide analogue". Carbohydrate Polymers. 380 125064. doi:10.1016/j.carbpol.2026.125064. PMID 41831981.
Sources: en.wikipedia.org
The principal difference is a chemical cap on the N-terminal tyrosine that prevents rapid enzymatic cleavage. Native GHRH is degraded within minutes in plasma, whereas the modified peptide persists considerably longer. The amino acid backbone otherwise mirrors the natural hormone.
No. It is a receptor agonist that stimulates the pituitary to release endogenous growth hormone. It does not contain or deliver growth hormone. Its downstream effects therefore depend on a functioning pituitary and an intact signaling pathway.
Pituitary responsiveness, receptor availability, and the natural pulsatility of the growth hormone axis all contribute. Because the compound amplifies an existing release pattern rather than overriding it, timing and physiological state matter. Individual variability in response is well documented but not fully explained.
tesamorelin 属 GHRH 类似物，作用于垂体受体以促进内源生长激素释放；生长激素本身是直接补充的外源激素。两者在给药逻辑、作用位点和反馈调控路径上并不相同。