Functional Role of Peptidergic Anterior Lobe Neurons in Male Sexual Behavior of the Snail Lymnaea stagnalis

1997 ◽  
Vol 78 (6) ◽  
pp. 2823-2833 ◽  
Author(s):  
Pamela A.C.M. De Boer ◽  
Andries Ter Maat ◽  
Anton W. Pieneman ◽  
Roger P. Croll ◽  
Makoto Kurokawa ◽  
...  

De Boer, Pamela A.C.M., Andries Ter Maat, Anton W. Pieneman, Roger P. Croll, Makoto Kurokawa, and René F. Jansen. Functional role of peptidergic anterior lobe neurons in male sexual behavior of the snail Lymnaea stagnalis. J. Neurophysiol. 78: 2823–2833, 1997. A morphologically defined group of peptidergic neurons in the CNS of the hermaphroditic snail, Lymnaea stagnalis, is concerned with the control of a very specific element of male sexual behavior. These neurons are located in the anterior lobe of the right cerebral ganglion (rAL). By using chronically implanted electrodes, we show that the rAL neurons are selectively active during eversion of the penis-carrying structure, the preputium. The preputium is normally contained inside the body cavity and is everted during copulation in the male role. Electrical stimulation of the rAL neurons through the implanted electrodes, induced eversion of the preputium in vivo. Injection of APGWamide (Ala-Pro-Gly-Try-NH2), a small neuropeptide that is present in all rAL neurons, induced eversion of the preputium. Application of APGWamide to in vitro preparations of the preputium caused relaxation of this organ. In contrast, injection of the neuropeptide conopressin, which is co-localized with APGWamide in 60% of the rAL neurons, did not induce any behavior associated with male sexual activities. These results show that the neurons of the rAL can induce an eversion of the preputium as occurs during male copulation by release of APGWamide during a period of electrical activity.

2012 ◽  
Vol 82 (3) ◽  
pp. 228-232 ◽  
Author(s):  
Mauro Serafini ◽  
Giuseppa Morabito

Dietary polyphenols have been shown to scavenge free radicals, modulating cellular redox transcription factors in different in vitro and ex vivo models. Dietary intervention studies have shown that consumption of plant foods modulates plasma Non-Enzymatic Antioxidant Capacity (NEAC), a biomarker of the endogenous antioxidant network, in human subjects. However, the identification of the molecules responsible for this effect are yet to be obtained and evidences of an antioxidant in vivo action of polyphenols are conflicting. There is a clear discrepancy between polyphenols (PP) concentration in body fluids and the extent of increase of plasma NEAC. The low degree of absorption and the extensive metabolism of PP within the body have raised questions about their contribution to the endogenous antioxidant network. This work will discuss the role of polyphenols from galenic preparation, food extracts, and selected dietary sources as modulators of plasma NEAC in humans.


2017 ◽  
Vol 312 (3) ◽  
pp. G219-G227 ◽  
Author(s):  
Leonie Beljaars ◽  
Sara Daliri ◽  
Christa Dijkhuizen ◽  
Klaas Poelstra ◽  
Reinoud Gosens

WNT-5A is a secreted growth factor that belongs to the noncanonical members of the Wingless-related MMTV-integration family. Previous studies pointed to a connection between WNT-5A and the fibrogenic factor TGF-β warranting further studies into the functional role of WNT-5A in liver fibrosis. Therefore, we studied WNT-5A expressions in mouse and human fibrotic livers and examined the relation between WNT-5A and various fibrosis-associated growth factors, cytokines, and extracellular matrix proteins. WNT-5A gene and protein expressions were significantly increased in fibrotic mouse and human livers compared with healthy livers. Regression or therapeutic intervention in mice resulted in decreased hepatic WNT-5A levels paralleled by lower collagen levels. Immunohistochemical analysis showed WNT-5A staining in fibrotic septa colocalizing with desmin staining indicating WNT-5A expression in myofibroblasts. In vitro studies confirmed WNT-5A expression in this cell type and showed that TGF-β significantly enhanced WNT-5A expression in contrast to PDGF-BB and proinflammatory cytokines IL-1β and TNF-α. Additionally, TGF-β induces the expression of the WNT receptors FZD2 and FZD8. After silencing of WNT-5A, reduced levels of collagen type I, vimentin, and fibronectin in TGF-β-stimulated myofibroblasts were measured compared with nonsilencing siRNA-treated controls. Interestingly, the antifibrotic cytokine IFNγ suppressed WNT-5A in vitro and in vivo. IFNγ-treated fibrotic mice showed significantly less WNT-5A expression compared with untreated fibrotic mice. In conclusion, WNT-5A paralleled collagen I levels in fibrotic mouse and human livers. WNT-5A expression in myofibroblasts is induced by the profibrotic factor TGF-β and plays an important role in TGF-β-induced regulation of fibrotic matrix proteins, whereas its expression can be reversed upon treatment, both in vitro and in vivo. NEW & NOTEWORTHY This study describes the localization and functional role of WNT-5A in human and mouse fibrotic livers. Hepatic WNT-5A expression parallels collagen type I expression. In vivo and in vitro, the myofibroblasts were identified as the key hepatic cells producing WNT-5A. WNT-5A is under control of TGF-β and its activities are primarily profibrotic.


1992 ◽  
Vol 162 (1) ◽  
pp. 107-130 ◽  
Author(s):  
LARRY M. FROLICH ◽  
ANDREW A. BIEWENER

Aquatic neotenic and terrestrial metamorphosed salamanders {Ambystoma tigrinum) were videotaped simultaneously with electromyographic (EMG) recording from five epaxial myotomes along the animal's trunk during swimming in a flow tank and trotting on a treadmill to investigate axial function during aquatic and terrestrial locomotion. Neotenic and metamorphosed individuals swim using very similar axial wave patterns, despite significant differences in axial morphology. During swimming, both forms exhibit traveling waves of axial flexion and muscle activity, with an increasing EMG-mechanical delay as these waves travel down the trunk. In contrast to swimming, during trotting metamorphosed individuals exhibit a standing wave of axial flexion produced by synchronous activation of ipsilateral epaxial myotomes along the trunk. Thus, metamorphosed individuals employ two distinct axial motor programs -- one used during swimming and one used during trotting. The transition from a traveling axial wave during swimming to a standing axial wave during trotting in A. tigrinum may be an appropriate analogy for similar transitions in axial locomotor function during theoriginal evolution of terrestriality in early tetrapods.


2020 ◽  
Vol 14 ◽  
Author(s):  
Diana Carolina Esquivel-Franco ◽  
Sietse F. de Boer ◽  
Marcel Waldinger ◽  
Berend Olivier ◽  
Jocelien D. A. Olivier

2020 ◽  
Vol 9 (1) ◽  
pp. 264 ◽  
Author(s):  
Laura Governini ◽  
Bianca Semplici ◽  
Valentina Pavone ◽  
Laura Crifasi ◽  
Camilla Marrocco ◽  
...  

Taste receptors (TASRs) are expressed not only in the oral cavity but also throughout the body, thus suggesting that they may play different roles in organ systems beyond the tongue. Recent studies showed the expression of several TASRs in mammalian testis and sperm, indicating an involvement of these receptors in male gametogenesis and fertility. This notion is supported by an impaired reproductive phenotype of mouse carrying targeted deletion of taste receptor genes, as well as by a significant correlation between human semen parameters and specific polymorphisms of taste receptor genes. To better understand the biological and thus clinical significance of these receptors for human reproduction, we analyzed the expression of several members of the TAS2Rs family of bitter receptors in human testis and in ejaculated sperm before and after in vitro selection and capacitation. Our results provide evidence for the expression of TAS2R genes, with TAS2R14 being the most expressed bitter receptor subtype in both testis tissue and sperm cells, respectively. In addition, it was observed that in vitro capacitation significantly affects both the expression and the subcellular localization of these receptors in isolated spermatozoa. Interestingly, α-gustducin and α-transducin, two Gα subunits expressed in taste buds on the tongue, are also expressed in human spermatozoa; moreover, a subcellular redistribution of both G protein α-subunits to different sub-compartments of sperm was registered upon in vitro capacitation. Finally, we shed light on the possible downstream transduction pathway initiated upon taste receptor activation in the male reproductive system. Performing ultrasensitive droplets digital PCR assays to quantify RNA copy numbers of a distinct gene, we found a significant correlation between the expression of TAS2Rs and TRPM5 (r = 0.87), the cation channel involved in bitter but also sweet and umami taste transduction in taste buds on the tongue. Even if further studies are needed to clarify the precise functional role of taste receptors for successful reproduction, the presented findings significantly extend our knowledge of the biological role of TAS2Rs for human male fertility.


2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Veronika Günther ◽  
Ibrahim Alkatout ◽  
Corinna Fuhs ◽  
Ali Salmassi ◽  
Liselotte Mettler ◽  
...  

Cytokines are key modulators of the immune system and play an important role in the ovarian cycle. IL-18 levels in serum and follicular fluid were analyzed in women undergoing in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) treatment. The cohort study group consisted of 90 women, who were undergoing IVF or ICSI. The body mass index (BMI) was determined in all patients; IL-18 levels were measured in follicular fluid and serum. IL-18 levels in serum were significantly higher than those in follicular fluid. The median level in serum was 162.75 (80.21) pg/mL and that in follicular fluid, 138.24 (91.78) pg/mL. Women undergoing IVF treatment had lower IL-18 levels in serum (median, 151.19 (90.73) pg/mL) than those treated with ICSI (median, 163.57 (89.97) pg/mL). The correlation between IL-18 levels in serum and BMI was statistically significant, as well as the correlation between IL-18 levels in follicular fluid and ovarian stimulation response (p=0.003). IL-18 was correlated with the response to ovarian stimulation and was the reason for successful pregnancy after IVF or ICSI treatment. Among other cytokines, IL-18 appears to be a promising prognostic marker of success in reproductive treatment and should be evaluated as such in further prospective studies.


2011 ◽  
Vol 84 (2) ◽  
pp. 239-248 ◽  
Author(s):  
Alan A. Sneddon

Selenium (Se) is an important dietary micronutrient required for sustaining optimal health. Se is incorporated into proteins, many of which are antioxidants that protect the body against oxidative damage. As oxidative damage may contribute to the development of chronic diseases including cardiovascular disease (CVD), Se has been proposed to provide a protective role against this disease. Studies in vitro and in animals continue to provide increasing insight into the role of Se in promoting vascular health and ameliorating CVD. Se within vascular cells limits the adhesion together of such cells, an important early step in the development of vascular disease. Organic forms of Se may also afford vascular cells greater protection against oxidative challenge compared to inorganic forms. Nevertheless, current studies in humans investigating the relationship between Se and CVD have so far proved equivocal; larger randomized trials with different Se exposures in populations spanning the broad physiological Se status are needed to determine the criteria whereby Se may influence CVD outcome within different populations. Further studies are also needed to explore the effects of different Se species and the role of different selenoprotein genotypes in modifying Se status and their resultant impact on cardiovascular function.


Cancers ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 587 ◽  
Author(s):  
Matilda Munksgaard Thorén ◽  
Katarzyna Chmielarska Masoumi ◽  
Cecilia Krona ◽  
Xiaoli Huang ◽  
Soumi Kundu ◽  
...  

New, effective treatment strategies for glioblastomas (GBMs), the most malignant and invasive brain tumors in adults, are highly needed. In this study, we investigated the potential of integrin α10β1 as a therapeutic target in GBMs. Expression levels and the role of integrin α10β1 were studied in patient-derived GBM tissues and cell lines. The effect of an antibody–drug conjugate (ADC), an integrin α10 antibody conjugated to saporin, on GBM cells and in a xenograft mouse model was studied. We found that integrin α10β1 was strongly expressed in both GBM tissues and cells, whereas morphologically unaffected brain tissues showed only minor expression. Partial or no overlap was seen with integrins α3, α6, and α7, known to be expressed in GBM. Further analysis of a subpopulation of GBM cells selected for high integrin α10 expression demonstrated increased proliferation and sphere formation. Additionally, siRNA-mediated knockdown of integrin α10 in GBM cells led to decreased migration and increased cell death. Furthermore, the ADC reduced viability and sphere formation of GBM cells and induced cell death both in vitro and in vivo. Our results demonstrate that integrin α10β1 has a functional role in GBM cells and is a novel, potential therapeutic target for the treatment of GBM.


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