Cell and Tissue Research最新文献

Odor detection in insects is largely mediated by structures on antennae called sensilla, which feature a strongly conserved architecture and repertoire of olfactory sensory neurons (OSNs) and various support cell types. In Drosophila, OSNs are tightly apposed to supporting cells, whose connection with neurons and functional roles in odor detection remain unclear. Coupling mechanisms between these neuronal and non-neuronal cell types have been suggested based on morphological observations, concomitant physiological activity during odor stimulation, and known interactions that occur in other chemosensory systems. For instance, it is not known whether cell-cell coupling via gap junctions between OSNs and neighboring cells exists, or whether hemichannels interconnect cellular and extracellular sensillum compartments. Here, we show that innexins, which form hemichannels and gap junctions in invertebrates, are abundantly expressed in adult drosophilid antennae. By surveying antennal transcriptomes and performing various immunohistochemical stainings in antennal tissues, we discover innexin-specific patterns of expression and localization, with a majority of innexins strongly localizing to glial and non-neuronal cells, likely support and epithelial cells. Finally, by injecting gap junction-permeable dye into a pre-identified sensillum, we observe no dye coupling between neuronal and non-neuronal cells. Together with evidence of non-neuronal innexin localization, we conclude that innexins likely do not conjoin neurons to support cells, but that junctions and hemichannels may instead couple support cells among each other or to their shared sensillum lymph to achieve synchronous activity. We discuss how coupling of sensillum microenvironments or compartments may potentially contribute to facilitate chemosensory functions of odor sensing and sensillum homeostasis.

Although the liver of the lamprey, a group of cyclostomes that diverged the earliest among vertebrates, has abundant bile ducts in the larval stage, which degenerate during metamorphosis, there is no comparative study on its architecture with other early diverged vertebrates in terms of the morphological evolution of vertebrate livers. The present study was undertaken to compare the characteristics of the brook lamprey liver with those of the hagfish and banded houndshark, which have the portal triad type liver architecture, and to discuss its evolution. Although the liver of the brook lamprey had two-cell cords of hepatocytes lined by sinusoids in the ammocoetes larval stage, intrahepatic bile ducts around portal veins penetrated into the liver parenchyma with convolution and gradual reduction in diameter. They also faced dilated sinusoids. The epithelial cells had characteristic intercellular spaces. These characteristics were distinct from those of bile ducts in the hagfish and banded houndshark livers. Although the liver architectures of the hagfish and banded houndshark were similar, the latter penetrated the intrahepatic bile ducts more deeply along the portal veins than the former, in which intrahepatic bile ducts were restricted near the hilum. After metamorphosis, bile ducts degenerated in brook lampreys. These data indicate that the liver architecture of the ammocoetes larva is unique in the parenchymal distribution of bile ducts, their sinusoidal facing, and morphology among extant vertebrates. The periportal distribution of intrahepatic biliary structures may have been established prior to the divergence of the cyclostomes and gnathostomes.

The olfactory organ of tetrapods, with few exceptions, comprises the main and accessory organs: olfactory epithelium (OE) and vomeronasal organ (VNO). Unlike tetrapods, teleost fish lack a VNO. However, lungfish, a type of sarcopterygian fish closely related to tetrapods, possesses a lamellar OE similar to the OE of teleosts and a recess epithelium (RecE) resembling the amphibian VNO. The RecE has been hypothesized as a primordial VNO. Olfactory receptors in tetrapods are distinctively expressed in the OE and VNO. For instance, type 2 vomeronasal receptors (V2Rs) in Xenopus are categorized into those exclusively expressed in the OE and those solely expressed in the VNO. It remains unclear whether V2Rs are differentially expressed between the lamellar OE and RecE in lungfish. This study investigated V2R expression in the lamellar OE and RecE of the African lungfish, Protopterus annectens. P. annectens V2Rs were categorized into three groups: those exclusively expressed in the lamellar OE, those exclusively expressed in the RecE, and those expressed in both the lamellar OE and RecE. V2Rs exclusively expressed in the RecE and those expressed in both the lamellar OE and RecE formed a distinct clade in the phylogenetic tree, whereas others were solely expressed in the lamellar OE. These findings suggest that lungfish V2R expression represents an intermediate stage toward complete segregation between V2Rs expressed in the OE and those expressed in the VNO.

This article commemorates the 100th anniversary of the first issue of Cell & Tissue Research (CTR), the longest-running active journal dedicated to cell biology. Reflecting the significant contributions of spermatology and embryology to the early days of cell biology, the majority of articles in CTR’s inaugural issue centered on plant and animal sperm cells. A brief synopsis of these articles provides a launching point for revisiting 100 years of research on the male germ cells and fertility in humans and animals and offers a perspective on the current state and future directions of the andrology field. Early technological advances in light and electron microscopy enabled descriptive studies that ushered in the era of mechanistic, biochemistry-based inquiry focused on the understanding of physiological sperm processes such as sperm capacitation, acrosomal exocytosis, and sperm-egg interactions. In the last 20 years, progress in flow cytometry, cell imaging, and omics revealed new information on sperm proteome, transcriptome, metabolome, and overall phenome of fertile and infertile spermatozoa. Going back to the journal’s roots, recent advances in male germ cell isolation, transplantation, modification, and cryopreservation have been discussed on the pages of CTR. Newest trends such as gene editing and artificial intelligence/machine learning are now making inroads into andrological inquiry and assisted reproductive therapy of male infertility.

This contribution highlights the scientific development of two intertwined disciplines, photoneuroendocrinology and circadian biology. Photoneuroendocrinology has focused on nonvisual photoreceptors that translate light stimuli into neuroendocrine signals and serve rhythm entrainment. Nonvisual photoreceptors first described in the pineal complex and brain of nonmammalian species are luminance detectors. In the pineal, they control the formation of melatonin, the highly conserved hormone of darkness which is synthesized night by night. Pinealocytes endowed with both photoreceptive and neuroendocrine capacities function as “photoneuroendocrine cells.” In adult mammals, nonvisual photoreceptors controlling pineal melatonin biosynthesis and pupillary reflexes are absent from the pineal and brain and occur only in the inner layer of the retina. Encephalic photoreceptors regulate seasonal rhythms, such as the reproductive cycle. They are concentrated in circumventricular organs, the lateral septal organ and the paraventricular organ, and represent cerebrospinal fluid contacting neurons. Nonvisual photoreceptors employ different photopigments such as melanopsin, pinopsin, parapinopsin, neuropsin, and vertebrate ancient opsin. After identification of clock genes and molecular clockwork, circadian biology became cutting-edge research with a focus on rhythm generation. Molecular clockworks tick in every nucleated cell and, as shown in mammals, they drive the expression of more than 3000 genes and are of overall importance for regulation of cell proliferation and metabolism. The mammalian circadian system is hierarchically organized; the central rhythm generator is located in the suprachiasmatic nuclei which entrain peripheral circadian oscillators via multiple neuronal and neuroendocrine pathways. Disrupted molecular clockworks may cause various diseases, and investigations of this interplay will establish a new discipline: circadian medicine.

The innervation of the antennal heart of the cockroach Periplaneta americana was studied with immunocytochemical techniques on both the light and electron microscopic levels. The antennal heart is innervated by two efferent systems, both using one biogenic amine in combination with neuropeptides. In one, we found co-localization of serotonin with proctolin and allatostatin. These fibers most likely originate from paired neurons located in the suboesophageal ganglion. In the second system, we found octopamine co-localized with the short neuropeptide F. The source of this second system is dorsal unpaired median (DUM) neurons, also located in the suboesophageal ganglion. The possible effects of these neuromediators on different targets are discussed.

The animal product most used as a stimulatory additive for cell cultivation is still fetal bovine serum (FBS). Besides the ethical concerns regarding serum collection, the main problems of FBS are batch-to-batch variability and the resulting risk of lower reproducibility, the differences between species, the presence of undefined/unknown components, and the risk of contamination. In contrast, pig blood, which is a by-product of slaughter, is a sufficiently available and sustainable resource with a high degree of standardization in terms of donor age, weight, and genetics. The variations in preparations from pig slaughter blood seem to be comparatively low, and consequently, batch effects might be much smaller, suggesting that the reproducibility of the research data obtained may be increased. Our pilot study aimed to investigate, as a proof of concept, whether adult human and porcine stem cells of different tissue origins proliferate and differentiate adequately when FBS is completely or partially replaced by porcine serum (PS). We could show that the human and porcine stem cells were vital and proliferated under partial and full PS supplementation. Furthermore, using PS, the two cell types studied showed tissue-specific differentiation (i.e., lipid vacuoles as a sign of adipogenic or myotubes as a sign of myogenic differentiation). In conclusion, the pig slaughter blood-derived serum has promising potential to be a replacement for FBS in adult stem cell cultures. Therefore, it could serve as a basis for the development of new cell culture supplements.

The complex interactome crucial for successful pregnancy is constituted by the intricate network of endocrine and paracrine signaling pathways, involving gametes, embryos, and the female reproductive tract. Specifically, the oviduct exhibits distinct responses to gametes and early embryos during particular phases of the estrus cycle, a process tightly regulated by reproductive hormones. Moreover, these hormones play a pivotal role in orchestrating cyclical changes within oviductal epithelial cells. To unravel the molecular mechanisms underlying these dynamic changes, our study aimed to investigate the involvement of protein kinase A (PKA) in oviductal epithelial cells throughout the estrus cycle and in advanced pregnancy, extending our studies to oviductal epithelial cell in primary culture. By a combination of 2D-gel electrophoresis, Western blotting, and mass spectrometry, we identified 17 proteins exhibiting differential phosphorylation status mediated by PKA. Among these proteins, we successfully validated the phosphorylation status of heat shock 70 kDa protein (HSP70), aconitase 2 (ACO2), and lamin B1 (LMNB1). Our findings unequivocally demonstrate the dynamic regulation of PKA throughout the estrus cycle in oviductal epithelial cells. Also, analysis by bioinformatics tools suggest its pivotal role in mediating cyclical changes possibly through modulation of apoptotic pathways. This research sheds light on the intricate molecular mechanisms underlying reproductive processes, with implications for understanding fertility and reproductive health.

Cisplatin nephrotoxicity is a well-known emergency clinical condition caused by oxidative stress and inflammation. Naringin (NAR) is considered an antioxidant agent with renoprotective effects capable of removing reactive oxygen species. Adipose tissue-derived mesenchymal stem cells (AD-MSCs) are reported to have anti-inflammatory and antioxidant properties. The present research examined the renoprotective effect of the combination of NAR and AD-MSCs as opposed to each one alone on cisplatin-induced nephrotoxicity through SIRT-1/Nrf-2/HO-1 pathway. This study included five groups (n = 8 each) of male Sprague-Dawley rats (200 - 220 g): sham, cisplatin: rats receiving cisplatin (6.5 mg/kg, i.p.) on the 4th day; NAR+cisplatin: rats pretreated with NAR (1 week, i.p.) + cisplatin on the 4th day; AD-MSCs: rats receiving AD-MSCs (1 × 10⁶) by injection through the tail vein on the 5th day + cisplatin on the 4th day; and NAR+AD-MSCs+cisplatin. On the 8th day, the animals were anesthetized to obtain tissue and blood samples. Biochemical factors, inflammation, oxidative stress, and gene expression were explored. Cisplatin increased blood urea nitrogen, creatinine, inflammation, and oxidative stress. Moreover, mRNA expression of Sirtuin1, nuclear factor erythroid 2-related factor 2 (Nrf-2), and heme oxygenase-1 (HO-1) remarkably reduced. Furthermore, cisplatin led to a disturbance in kidney structure (glomerular atrophy, cell infiltrations, and tubular dysfunction) as confirmed by histology findings. However, NAR pretreatment, AD-MSC administration, or a combination of both significantly reversed these changes. Overall, when used together, NAR and AD-MSCs had stronger cisplatin-induced effects on kidney dysfunction by inhibiting inflammation, reducing oxidative stress, and increasing the Sirtuin1/Nrf-2/HO-1 pathway.

Chemical communication through olfaction is crucial for fish behaviours, mediating in socio-sexual behaviours as reproduction. Turbot, a flatfish with significant aquaculture production, possesses a well-developed olfactory system from early developmental stages. After metamorphosis, flatfish acquire their characteristic bilateral asymmetry with an ocular side facing the open water column, housing the dorsal olfactory rosette, and a blind side in contact with the sea bottom where the ventral rosette is located. This study aimed to address the existing gap in specific histological, ultrastructural, lectin-histochemical and immunohistochemical studies of the turbot olfactory rosettes and olfactory bulbs. We examined microdissected olfactory organs of adult turbots and premetamorphic larvae by using routine histological staining techniques, and a wide array of lectins and primary antibodies against G-proteins and calcium-binding proteins. We observed no discernible structural variations in the olfactory epithelium between rosettes, except for the dorsal rosette being larger in size compared to the ventral rosette. Additionally, the use of transmission electron microscopy significantly improved the characterization of the adult olfactory epithelium, exhibiting high cell density, small cell size, and a wide diversity of cell types. Moreover, specific immunopositivity in sensory and non-sensory cells provided us of essential information regarding their olfactory roles. The results obtained significantly enriched the scarce morphological and neurochemical information available on the turbot olfactory system, revealing a highly complex olfactory epithelium with distinct features compared to other teleost species, especially with regard to olfactory cell distribution and immunolabelling patterns.