Regulation of Reproduction by Dopamine
Nira Ben-Jonathan in Dopamine, 2020
The testes also produce several protein hormones that include activin, inhibin, and follistatin [26]. Inhibins are released into the blood and suppress pituitary FSH secretion, whereas activins mostly exert their actions as local paracrine/autocrine growth factors. Follistatin is a potent activin binding protein, which also modulates local biological functions. Inhibin is a dimeric glycoprotein existing in two bioactive forms: A and B. Inhibin B shows temporal changes in its expression with the changing role of the Sertoli cell in immature and adult testes. In the adult, the levels of inhibin B are positively correlated with sperm number and spermatogenic status and are negatively correlated with serum FSH levels. Production of inhibin B is regulated by complex interactions between FSH, Sertoli cells, Leydig cells, and germ cells. Inhibin may also play a role at autocrine or paracrine levels in modulating the actions of activin. Other compounds such as opioids, GnRH-like peptides, vasopressin, oxytocin, and several growth factors have also been detected in the testes and appear to function as paracrine agents.
Gonadotropins in the Male
Paul V. Malven in Mammalian Neuroendocrinology, 2019
Blood-borne inhibin secreted in response to FSH action on Sertoli cells exerts inhibitory feedback on FSH release in the male (see next paragraph). Testosterone secreted by the interstitial cells may also participate in FSH secretion, but this action is largely mediated by suppression of LHRH release that affects both LH and FSH. Another putative inhibitor of FSH secretion in males and females is a linear glycoprotein known as follistatin. Although follistatin can inhibit FSH as does inhibin, it also binds to inhibin and decreases its FSH-inhibiting potency. The mRNA encoding follistatin is present in various tissues including the adenohypophysis where it occurs in gonadotrophs as well as a specific cell type known as the folliculostellate cell (Kaiser et al., 1992). Because inhibin, activin, follistatin, and FSH have all been shown to coexist in gonadotrophs, complex paracrine/autocrine control of FSH release becomes a realistic possibility.
Hormones and their Effects on the Cardiovascular System
Stephen T. Sinatra, Mark C. Houston in Nutritional and Integrative Strategies in Cardiovascular Medicine, 2015
Some scientists believe that PCOS has a hereditary component.73,74 It is noted that 40% of women with PCOS have a sister with PCOS. Further, 35% of women with PCOS have a mother with PCOS.89 There is a suggestion in the medical literature that women with PCOS are born with a gene that triggers higher than normal levels of androgens or insulin.90,91 Studies have also shown that the high levels of testosterone and insulin in patients with PCOS are lined by a gene called follistatin. Follistatin plays a role in the development of ovaries and is needed to make insulin.92 Furthermore, phthalates, bisphenol A, cadmium, and mercury toxicities may be related to the development of PCOS because they are endocrine disrupters.94
The effects of gradual vs. rapid weight loss on serum concentrations of myokines and body composition in overweight and obese females
Published in Archives of Physiology and Biochemistry, 2023
Reza Bagheri, Damoon Ashtary-Larky, Bradley T Elliott, Darryn S. Willoughby, Mehdi Kargarfard, Meysam Alipour, Nasrin Lamuchi-Deli, Wesam Kooti, Omid Asbaghi, Alexei Wong
MST is a member of transforming growth factor-beta (TGF-β) family member which inhibits muscle differentiation and growth (Allen et al. 2011). Mice in which MST processing or signalling is disrupted exhibited muscle mass gains (Yang et al. 2001, Matsakas et al. 2009), while MST over-expression resulted in a significant decrements of muscle mass (Reisz-Porszasz et al. 2003). These results confirm MST’s critical role in inhibiting muscle mass gains. Follistatin is a member of the TGF-β superfamily (Görgens et al. 2013), which is ubiquitously expressed in all tissues of the human body, including skeletal muscle, and has both paracrine and autocrine influences. FST has shown to bind MST and inhibit its activity (Nakatani et al. 2011), but also can bind and inhibit other TGF-β family members (Tsuchida et al. 2000), suggesting a more diverse physiological role. Obesity is associated with increased MST expression in both adipose and skeletal muscle tissues (Allen et al. 2011), and MST mRNA levels decreased during weight loss following daily injection of recombinant leptin in mice (Allen et al. 2008). Similarly, circulating FST concentration is also elevated in obese individuals relative to normal weight controls (Maïmoun et al. 2020), concentration of which is subsequently reduced following bariatric surgery-induced weight loss (Wiewiora et al. 2020). These results highlight a role of weight loss to reduce MST and FST concentrations.
Inflammatory myopathies: shedding light on promising agents and combination therapies in clinical trials
Published in Expert Opinion on Investigational Drugs, 2021
Rachel Zeng, Stefanie Glaubitz, Jens Schmidt
Follistatin antagonizes the effects of myostatin and thereby promotes skeletal muscle growth. As this bears the potential to treat muscle atrophy, a novel gene therapy with AAV vectors encoding a follistatin isoform was tested in a small open-label study with six male IBM patients [95]. The treatment was injected in the quadriceps muscles of both legs. Improvement in the 6MWD was the primary outcome. Additionally, all patients had an exercise regime three times a week. After one year of the injection-treated patients showed mild improvement in the 6MWT compared to untreated patients, who were matched for gender and age, but these results need to interpreted very carefully in view of this very low number of patients. The posttreatment muscle biopsy showed reduced fibrosis and increased muscle regeneration.
Effects of acute sprint interval exercise on follistatin-like 1 and apelin secretions
Published in Archives of Physiology and Biochemistry, 2021
Michihiro Kon, Yoshiko Ebi, Kohei Nakagaki
In recent years, skeletal muscle tissue has been recognized as an important secretion source of cytokines (hence, named myokines) such as interleukin (IL)-6 and IL-15 (Pedersen and Febbraio 2008). Follistatin-like 1 (FSTL1) (Lee et al. 2017) and apelin (Dray et al. 2008, Yue et al. 2010) are novel myokines that have recently been indicated as being related to glucose metabolism in skeletal muscle. FSTL1 is a secreted glycoprotein belonging to a member of the follistatin family (Sumitomo et al. 2000). In an in vitro study using skeletal muscle cells, FSTL1 stimulated GLUT4 translocation into the plasma membrane and increased glucose uptake (Lee et al. 2017). Apelin, which is a novel bioactive peptide hormone, presented and secreted from various tissues including skeletal muscle (Tatemoto et al. 1998). Dray et al. (2008) have demonstrated that intravenous injection of apelin enhanced glucose utilization in skeletal muscle. In addition, knocking out apelin impaired insulin sensitivity and decreased insulin sensitivity was improved by exogenous administration of apelin (Yue et al. 2010). These results suggest that FSTL1 and apelin are related to glucose metabolism in skeletal muscle and have improvement effect against insulin sensitivity. Although FSTL1 and apelin may be associated with the SIT-induced improvement effects on glucose metabolism and insulin sensitivity, the effect of SIT on FSTL1 and apelin secretions has not been examined.
Related Knowledge Centers
- Activin & Inhibin
- Anterior Pituitary
- Autocrine Signaling
- Paracrine Signaling
- Protein
- Glycoprotein
- Gene
- Transforming Growth Factor Beta Superfamily
- Activin & Inhibin
- Follicular Fluid
- Follicle-Stimulating Hormone