Spermatogonial stem cell sensitivity to capsaicin: An in vitro study

<p>Abstract</p> <p>Background</p> <p>Conflicting reports have been published on the sensitivity of spermatogenesis to capsaicin (CAP), the pungent ingredient of hot chili peppers. Here, the effect of CAP on germ cell survival was investigated by using two testis germ cell lines as a model. As CAP is a potent agonist of the transient receptor potential vanilloid receptor 1 (TRPV1) and no information was available of its expression in germ cells, we also studied the presence of TRPV1 in the cultured cells and in germ cells in situ.</p> <p>Methods</p> <p>The rat spermatogonial stem cell lines Gc-5spg and Gc-6spg were used to study the effects of different concentrations of CAP during 24 and 48 h. The response to CAP was first monitored by phase-contrast microscopy. As germ cells appear to undergo apoptosis in the presence of CAP, the activation of caspase 3 was studied using an anti activated caspase 3 antibody or by quantifying the amount of cells with DNA fragmentation using flow cytometry. Immunolocalization was done with an anti-TRPV1 antibody either with the use of confocal microscopy to follow live cell labeling (germ cells) or on Bouin fixed paraffin embedded testicular tissues. The expression of TRPV1 by the cell lines and germ cells was confirmed by Western blots.</p> <p>Results</p> <p>Initial morphological observations indicated that CAP at concentrations ranging from 150 uM to 250 uM and after 24 and 48 h of exposure, had deleterious apoptotic-like effects on both cell lines: A large population of the CAP treated cell cultures showed signs of DNA fragmentation and caspase 3 activation. Quantification of the effect demonstrated a significant effect of CAP with doses of 150 uM in the Gc-5spg cell line and 200 uM in the Gc-6spg cell line, after 24 h of exposure. The effect was dose and time dependent in both cell lines. TRPV1, the receptor for CAP, was found to be expressed by the spermatogonial stem cells in vitro and also by premeiotic germ cells in situ.</p> <p>Conclusion</p> <p>CAP adversely affects spermatogonial survival in vitro by inducing apoptosis to those cells and TRPV-1, a CAP receptor, may be involved in this effect as this receptor is expressed by mitotic germ cells.</p

Investigations on morphological and histochemical properties of motor nerve endings in tail muscles of trout

Çalışmada, alabalıklarda kuyruğun hızlı hareketini sağlayan kuyruk kaslarının güçlü kasılma yeteneğini açıklayabilmek için kuyruk bölgesi kas fibrillerinin ve bu fibrill erdeki sinir-kas ilişkilerinin incelenmesi amaçlandı. Alabalıkların kuyruk bölgesi kaslarının yapısal özellikleri, sinir sonlarının tipleri ve biçimleri ışık mikroskobik düzeyde incelendi. Alabalığın kuyruk bölgesinde bulunan 7 kastan hazırlanan preparatlar incelendiğinde m. lateralis superfisialis'in küçük çaplı kırmızı kas fibril lerinden oluştuğu görüldü. M. lateralis superfisialis dışında kalan diğer 6 kas grubunun çoğunluğunun büyük çaplı beyaz kas fibrillerinden oluştuğu ve bunların aralarında intermediyet tip kas fibrillerinin yer aldığı saptandı. Bu kas f ibrillerinden başka küçük çaplı üçgen şekilli miyosatellit hücrelerinin de mevcut olduğu tespit edildi. M. lateralis superfisialis 'i oluşturan kırmızı kas fibrillerinin horizontal septum bölgesinde 2 katman halinde bulunduğu, çaplarının yaklaşık 16-17 mikron olduğu, bol miktarda lipid içerdikleri ve innervasyonun multiple ve end plate tip sinir sonları ile sağlandığı tespit edildi. Alabalıklarda m. lateralis superfisialis dışında kalan 1diğer kuyruk bölgesi kaslarında yaygın olarak bulunan ortalama 70-100 mikron çapa sahip, lipid yönünden fakir olan beyaz kas fibrillerinin multiple ve end grappe tip sinir sonları ile innerve olduğu görüldü. Ayrıca sadece beyaz kas fibril lerinde sinir sonları dışında kalan bölgelerde endomizyumun AChE pozitif reaksiyon verdiği saptandı.In this study, muscle fibers of tail and neuro-muscular relations of fibers were investigated in order to define the capability of strong contraction of trout (Salmo irideus gairdneri) tail muscles which provided rapid tail movements. Structural properties, shapes and types of motor nerve terminals of tail muscles were observed by the light microscopy. In the light of the examinations of slided taken from 7 different muscles of tail region, it was observed that, m. lateralis superf icialis was formed from small diameter red muscles fibers whereas the larger part of the other 6 muscles were formed from large diameter white fibers. Meanwhile, intermediate type muscle fibers were found among these muscles. In addition to them, small, triangled myosatellite cells were observed too. It has been established that the red muscles fibers of m. laterales superficialis consisted of two layers at the horizontal septal region and their diameters were approximately 16-17 micrones and that they contained a large quantity of lipid and the innervation occured by multiple and end plate type. 3White muscle fibers which are extensively found in the other muscles of the tail in trout, except m. lateralis superf icialis, with a diameter of 100 microns, poor in lipid are innerved by multiple and end grappe type nerve terminals. Also, it has been determined that endomysium had positive AChE activity only in white muscle fibres in the other regions except nerve terminals

Histološka istraživanja sjemenika miša nakon primjene kapsaicina

In the present study we examined the effects of capsaicin, a pungent principle of red hot pepper, on mice testes. Capsaicin was injected subcutaneously at a dose of 1 mg/kg body means everyday for a week each time on 21, 35 and 50-day-olds respectively. The body and testes means of all mice comprising the experiment groups were higher than the control groups. The intertubular compartment of the testes in both group mice showed ++ positive reaction with Oil Red O staining. Spermatogenic cell serial formation took place earlier compared to the control group. Our study results indicate that capsaicin is relatively non toxic at this dose (1 mg/kg body mean) tested in male mice, no mortality was observed during the study, the experiment groups were hyperactive and spermatogenic series develop earlier.Istraženi su učinci kapsaicina, jetkog i glavnog sastojka crvenoga papra, na sjemenike miševa. Kapsaicin je bio primijenjen miševima u dobi od 21, 35 i 50 dana supkutano u dozi od 1 mg/kg tjelesne mase svakoga dana u tjednu. Prosječna tjelesna masa i masa sjemenika u miševa pokusnih skupina bila je veća nego u kontrolnih skupina. Intertubularni odjeljci sjemenika obiju skupina miševa pokazivali su ++ pozitivnu reakciju bojenjem uljnim crvenilom. Spermatogene stanice oblikovale su se ranije u pokusnoj skupini u odnosu na kontrolnu. Rezultati pokazuju da je kapsaicin relativno netoksičan u miševa u dozi od 1 mg/kg tjelesne mase. Tijekom istraživanja uginuća nisu bila zabilježena. Životinje pokusne skupine bile su hiperaktivne s ranije razvijenim spermatogenim stanicama

Intracerebroventricularly injected nesfatin-1 activates central cyclooxygenase and lipoxygenase pathways.

Nesfatin-1 is a multifunctional neuropeptide having crucial autonomic roles. It is well known that nesfatin-1 collaborates with other central neuromodulatory systems, such as central corticotropin-releasing hormone, melanocortin, oxytocin, and cholinergic systems to show its autonomic effects. Central arachidonic acid cascade plays an important role to provide the homeostasis by exhibiting similar autonomic effects to nesfatin-1. Based on these similarities, the current study was designed to show the effects of intracerebroventricularly (ICV) injected nesfatin-1 on the hypothalamic arachidonic acid (AA) cascade