scholarly journals Sex and Regeneration

Biology ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 937
Author(s):  
Moshe Reuveni
Keyword(s):  
Sex Hormones ◽  
Animal Species ◽  
Reproductive Status ◽  
Whole Body ◽  
Regeneration Capacity ◽  
Evolution Of Life ◽  
Ability To Regenerate ◽  
Sexual State ◽  
Regenerate Tissue ◽  
Multicellular Organisms

Regeneration is usually regarded as a unique plant or some animal species process. In reality, regeneration is a ubiquitous process in all multicellular organisms. It ranges from response to wounding by healing the wounded tissue to whole body neoforming (remaking of the new body). In a larger context, regeneration is one facet of two reproduction schemes that dominate the evolution of life. Multicellular organisms can propagate their genes asexually or sexually. Here I present the view that the ability to regenerate tissue or whole-body regeneration is also determined by the sexual state of the multicellular organisms (from simple animals such as hydra and planaria to plants and complex animals). The above idea is manifested here by showing evidence that many organisms, organs, or tissues show inhibited or diminished regeneration capacity when in reproductive status compared to organs or tissues in nonreproductive conditions or by exposure to sex hormones.

scholarly journals Perspective on Sex and Regeneration

2021 ◽  
Author(s):  
Moshe Reuveni
Keyword(s):  
Sex Hormones ◽  
Animal Species ◽  
Reproductive Status ◽  
Whole Body ◽  
Regeneration Capacity ◽  
Evolution Of Life ◽  
Ability To Regenerate ◽  
Sexual State ◽  
Regenerate Tissue ◽  
Multicellular Organisms

Regeneration is usually regarded as a unique plant or some animal species process. In reality, regeneration is a ubiquitous process in all multicellular organisms. It ranges from response to wounding by healing the wounded tissue to whole body neoforming (remaking of the new body). In a larger context, regeneration is one facet of two reproduction schemes that dominate the evolution of life. Multicellular organisms can propagate their genes asexually or sexually. Here I present the view that the ability to regenerate tissue or whole-body regeneration is also determined by the sexual state of the multicellular organisms (from simple animals like hydra and planaria to plants and complex animals). The above idea is manifested here by showing evidence that many organisms, organs, or tissues show inhibited or diminished regeneration capacity when in reproductive status compared to the same organism organs or tissues in nonreproductive conditions or by exposure to sex hormones.

scholarly journals Regeneration in the ctenophore Mnemiopsis leidyi occurs in the absence of a blastema, requires cell division, and is temporally separable from wound healing

BMC Biology ◽  
2019 ◽  
Vol 17 (1) ◽  
Author(s):  
Julia Ramon-Mateu ◽  
S. Tori Ellison ◽  
Thomas E. Angelini ◽  
Mark Q. Martindale
Keyword(s):  
Cell Proliferation ◽  
Wound Healing ◽  
Healing Process ◽  
Whole Body ◽  
Local Source ◽  
Mnemiopsis Leidyi ◽  
Wound Healing Process ◽  
Marine Animals ◽  
High Fecundity ◽  
Ability To Regenerate

Abstract Background The ability to regenerate is a widely distributed but highly variable trait among metazoans. A variety of modes of regeneration has been described for different organisms; however, many questions regarding the origin and evolution of these strategies remain unanswered. Most species of ctenophore (or “comb jellies”), a clade of marine animals that branch off at the base of the animal tree of life, possess an outstanding capacity to regenerate. However, the cellular and molecular mechanisms underlying this ability are unknown. We have used the ctenophore Mnemiopsis leidyi as a system to study wound healing and adult regeneration and provide some first-time insights of the cellular mechanisms involved in the regeneration of one of the most ancient extant group of multicellular animals. Results We show that cell proliferation is activated at the wound site and is indispensable for whole-body regeneration. Wound healing occurs normally in the absence of cell proliferation forming a scar-less wound epithelium. No blastema-like structure is generated at the cut site, and pulse-chase experiments and surgical intervention show that cells originating in the main regions of cell proliferation (the tentacle bulbs) do not seem to contribute to the formation of new structures after surgical challenge, suggesting a local source of cells during regeneration. While exposure to cell-proliferation blocking treatment inhibits regeneration, the ability to regenerate is recovered when the treatment ends (days after the original cut), suggesting that ctenophore regenerative capabilities are constantly ready to be triggered and they are somehow separable of the wound healing process. Conclusions Ctenophore regeneration takes place through a process of cell proliferation-dependent non-blastemal-like regeneration and is temporally separable of the wound healing process. We propose that undifferentiated cells assume the correct location of missing structures and differentiate in place. The remarkable ability to replace missing tissue, the many favorable experimental features (e.g., optical clarity, high fecundity, rapid regenerative performance, stereotyped cell lineage, sequenced genome), and the early branching phylogenetic position in the animal tree, all point to the emergence of ctenophores as a new model system to study the evolution of animal regeneration.

scholarly journals Major evolutionary transitions in individuality

2015 ◽  
Vol 112 (33) ◽  
pp. 10112-10119 ◽  
Author(s):  
Stuart A. West ◽  
Roberta M. Fisher ◽  
Andy Gardner ◽  
E. Toby Kiers
Keyword(s):  
Life Form ◽  
Cooperative Groups ◽  
Evolutionary Transitions ◽  
Major Transitions ◽  
Number Of Factors ◽  
Key Points ◽  
Evolution Of Life ◽  
Life On Earth ◽  
Multicellular Organisms ◽  
Unified Description

The evolution of life on earth has been driven by a small number of major evolutionary transitions. These transitions have been characterized by individuals that could previously replicate independently, cooperating to form a new, more complex life form. For example, archaea and eubacteria formed eukaryotic cells, and cells formed multicellular organisms. However, not all cooperative groups are en route to major transitions. How can we explain why major evolutionary transitions have or haven’t taken place on different branches of the tree of life? We break down major transitions into two steps: the formation of a cooperative group and the transformation of that group into an integrated entity. We show how these steps require cooperation, division of labor, communication, mutual dependence, and negligible within-group conflict. We find that certain ecological conditions and the ways in which groups form have played recurrent roles in driving multiple transitions. In contrast, we find that other factors have played relatively minor roles at many key points, such as within-group kin discrimination and mechanisms to actively repress competition. More generally, by identifying the small number of factors that have driven major transitions, we provide a simpler and more unified description of how life on earth has evolved.

scholarly journals Regeneration in the absence of a blastema requires cell division but is not tied to wound healing in the ctenophore Mnemiopsis leidyi

2019 ◽  
Author(s):  
Julia Ramon-Mateu ◽  
Tori Ellison ◽  
Thomas E. Angelini ◽  
Mark Q. Martindale
Keyword(s):  
Cell Proliferation ◽  
Wound Healing ◽  
Healing Process ◽  
Whole Body ◽  
Local Source ◽  
Mnemiopsis Leidyi ◽  
Wound Healing Process ◽  
Marine Animals ◽  
High Fecundity ◽  
Ability To Regenerate

ABSTRACTBackgroundThe ability to regenerate is a widely distributed but highly variable trait among metazoans. A variety of modes of regeneration has been described for different organisms, however, many questions regarding the origin and evolution of these strategies remain unanswered. Most species of ctenophore (or “comb jellies”), a clade of marine animals that branch off at the base of the animal tree of life, possess an outstanding capacity to regenerate. However, the cellular and molecular mechanisms underlying this ability are unknown. We have used the ctenophore Mnemiopsis leidyi as a system to study wound healing and adult regeneration and provide some first-time insights of the cellular mechanisms involved in the regeneration of one of the most ancient extant group of multicellular animals.ResultsWe show that cell proliferation is activated at the wound site and is indispensable for whole-body regeneration. Wound healing occurs normally in the absence of cell proliferation forming a scar-less wound epithelium. No blastema-like structure is generated at the cut site, rather undifferentiated cells assume the correct location of missing structures and differentiate in place. Pulse-chase experiments and surgical intervention show that cells originating in the main regions of cell proliferation (the tentacle bulbs) do not seem to contribute to the formation of new structures after surgical challenge, suggesting a local source of cells during regeneration. While exposure to cell-proliferation blocking treatment inhibits regeneration, the ability to regenerate is recovered when the treatment ends (days after the original cut), suggesting that ctenophore regenerative capabilities are constantly ready to be triggered and they are somehow separable of the wound healing process.ConclusionsCtenophore regeneration takes place through a process of cell proliferation-dependent non blastemal-like regeneration and is temporally separable of the wound healing process. The remarkable ability to replace missing tissue, the many favorable experimental features (e.g. optical clarity, high fecundity, rapid regenerative performance, stereotyped cell lineage, sequenced genome), and the early branching phylogenetic position in the animal tree, all point to the emergence of ctenophores as a new model system to study the evolution of animal regeneration.

scholarly journals A modern view of pro-/eukaryote interactions in the human body as the basis for development of next-generation probiotics

2020 ◽  
Vol 97 (4) ◽  
pp. 346-355
Author(s):  
Natalia A. Mikhailova ◽  
Dmitry A. Voevodin ◽  
Sergey A. Lazarev
Keyword(s):  
Human Body ◽  
Pathological Process ◽  
Whole Body ◽  
Functional Rehabilitation ◽  
Form Complex ◽  
Regulatory Processes ◽  
Normal Microflora ◽  
Artificial Environment ◽  
Long Time ◽  
Multicellular Organisms

Multicellular organisms and the saprophytic flora form complex, highly integrated chimeric systems (associative symbioses, metaorganisms) characterized by interplay between pro- and eukaryotic components. To be able to interact symbiotically microorganisms (MO) need a whole body.When grown on artificial media for a long time, symbiotic MO have to adapt to the artificial environment and gradually, though reversibly, lose their ability of associative interaction with the human body, thus causing a decrease in the therapeutic efficacy of MO-derived probiotic products. To increase the therapeutic activity of probiotic MO, they must be functionally rehabilitated.A pathological process induces development of a secondary metabolic dysbiosis; as a result, changes in the regulatory processes of an individual interfere with the restoration of the normal microflora. Therefore, functional rehabilitation of probiotic MO must take place during cultivation, while the cultivation process must replicate the whole-body conditions.

Effect of Occupational Exposure to Whole-Body Vibration and Noise on Sex Hormone Levels: A Case Study in an Automobile Parts Manufacturing Plant

2020 ◽  
Author(s):  
Hamzeh Mohammadi ◽  
Farideh Golbabaei ◽  
Somayeh Farhang Dehghan ◽  
Soheila Khodakarim Ardakani ◽  
Hossein Imani ◽  
...  
Keyword(s):  
Sex Hormones ◽  
Noise Exposure ◽  
Whole Body Vibration ◽  
Sex Hormone ◽  
Whole Body ◽  
Manufacturing Plant ◽  
Blood Samples ◽  
Testosterone Levels ◽  
Parts Manufacturing ◽  
The Relationship

Abstract Background: The present study investigated the effects of exposure to noise and whole body vibration (WBV) on the levels of sex hormones in an automobile parts manufacturing plant.Methods: The level of workers' exposure (n=162) to each of the mentioned stressors, was measured through standard methods and for each person the time-weighted average (TWA) of exposure was calculated. In order to determine serum sex hormones (free testosterone, LH and FSH), blood samples were taken from all participants after 8-10 hours of fasting between 7-9 am and then the blood samples were analyzed by ELISA method. Results: In general, regarding testosterone as the main male sex hormone, only 49% of the participants were in the normal range. In total of three sections, the lowest mean testosterone levels was observed in the third exposure group (WBV>1.93 m/s2; noise >92.69 dB) of the studied stressor, however, only the difference in testosterone levels between the three different groups of exposure to noise was statistically significant (P = 0.001). The relationship between demographic variables and levels of noise and WBV exposure with sex hormones was not linear and only the relationship between noise exposure and testosterone levels was statistically significant (R = -0.201, P = 0.013). Conclusion: According to the results of Logistic Regression, the WBV had the greatest effect on testosterone levels as the main male hormone. However, according to the results of the correlation test, only the relationship between noise exposure and testosterone levels is statistically significant.

The roles of signaling pathways in cardiac regeneration

2021 ◽  
Vol 28 ◽  
Author(s):  
Amir Valizadeh ◽  
Samira Asghari ◽  
Parinaz Mansouri ◽  
Forough Alemi ◽  
Maryam Majidinia ◽  
...  
Keyword(s):  
Signaling Pathways ◽  
Animal Species ◽  
Cell Communication ◽  
Cardiac Regeneration ◽  
Cardiac Repair ◽  
Regeneration Capacity ◽  
Disease Treatment ◽  
Model Studies ◽  
Vegf Signaling

: In recent years, knowledge of cardiac regeneration mechanisms has dramatically expanded. Regeneration can replace lost parts of organs, common among animal species. The heart is commonly considered an organ with terminal development, which has no reparability potential during post-natal life; however, some intrinsic regeneration capacity has been reported for cardiac muscle, which opens novel avenues in cardiovascular disease treatment. Different endogenous mechanisms were studied for cardiac repairing and regeneration in recent decades. Survival, proliferation, inflammation, angiogenesis, cell-cell communication, cardiomyogenesis, and anti-aging pathways are the most important mechanisms that have been studied in this regard. Several in vitro and animal model studies focused on proliferation induction for cardiac regeneration reported promising results. These studies have mainly focused on promoting proliferation signaling pathways and demonstrated various signaling pathways such as Wnt, PI3K/Akt, IGF-1, TGF-β, Hippo, and VEGF signaling cardiac regeneration. Therefore, in this review, we intended to discuss the connection between different critical signaling pathways in cardiac repair and regeneration.

DISTRIBUTION OF RADIOACTIVITY IN THE ORGANS OF THE RAT AND MOUSE AFTER INJECTION OF l-[3H]PROLYL-l-LEUCYL-GLYCINAMIDE

1975 ◽  
Vol 64 (2) ◽  
pp. 243-NP ◽  
Author(s):  
A. DUPONT ◽  
F. LABRIE ◽  
G. PELLETIER ◽  
R. PUVIANI ◽  
D. H. COY ◽  
...  
Keyword(s):  
Adrenal Gland ◽  
Pineal Gland ◽  
Direct Measurement ◽  
Anterior Pituitary ◽  
Animal Species ◽  
Submaxillary Gland ◽  
Whole Body ◽  
Intermediate Lobe ◽  
Preferential Uptake ◽  
Good Agreement

SUMMARY The distribution of radioactivity after intrajugular injection of l-[3H]prolyl-l-leucyl-glycinamide has been studied by whole-body autoradiography in the mouse and by direct measurement of radioactivity in individual organs of the rat. There is good agreement between results obtained with the two techniques and animal species. High levels of radioactivity were found in the pineal gland, anterior pituitary, posterior (including intermediate) lobe of the pituitary, and epididymal and brown fat. Lower uptake of radioactivity occurred in the submaxillary gland, kidney, and adrenal gland. The preferential uptake of radioactivity by the pineal gland after injection of the labelled tripeptide suggests a role for this hypothalamic hormone in the control of pineal activity.

scholarly journals Infection and cancer in multicellular organisms

2015 ◽  
Vol 370 (1673) ◽  
pp. 20140224 ◽  
Author(s):  
Paul W. Ewald ◽  
Holly A. Swain Ewald
Keyword(s):  
Animal Species ◽  
Low Frequency ◽  
Domestic Animals ◽  
Malignant Neoplasms ◽  
Infectious Agents ◽  
Oncogenic Transformation ◽  
Short Survival ◽  
Uncertain Evidence ◽  
Multicellular Organisms

Evolutionary considerations suggest that oncogenic infections should be pervasive among animal species. Infection-associated cancers are well documented in humans and domestic animals, less commonly reported in undomesticated captive animals, and rarely documented in nature. In this paper, we review the literature associating infectious agents with cancer to evaluate the reasons for this pattern. Non-malignant infectious neoplasms occur pervasively in multicellular life, but oncogenic progression to malignancy is often uncertain. Evidence from humans and domestic animals shows that non-malignant infectious neoplasms can develop into cancer, although generally with low frequency. Malignant neoplasms could be difficult to find in nature because of a low frequency of oncogenic transformation, short survival after malignancy and reduced survival prior to malignancy. Moreover, the evaluation of malignancy can be ambiguous in nature, because criteria for malignancy may be difficult to apply consistently across species. The information available in the literature therefore does not allow for a definitive assessment of the pervasiveness of infectious cancers in nature, but the presence of infectious neoplasias and knowledge about the progression of benign neoplasias to cancer is consistent with a widespread but largely undetected occurrence.

scholarly journals Comparative Aspects of Annelid Regeneration: Towards Understanding the Mechanisms of Regeneration

Genes ◽  
2021 ◽  
Vol 12 (8) ◽  
pp. 1148
Author(s):  
Roman P. Kostyuchenko ◽  
Vitaly V. Kozin
Keyword(s):  
Tissue Regeneration ◽  
Molecular Basis ◽  
The Other ◽  
Whole Body ◽  
Descriptive Data ◽  
Transcriptomic Data ◽  
Levels Of Organization ◽  
Ability To Regenerate ◽  
Different Levels

The question of why animals vary in their ability to regenerate remains one of the most intriguing questions in biology. Annelids are a large and diverse phylum, many members of which are capable of extensive regeneration such as regrowth of a complete head or tail and whole-body regeneration, even from few segments. On the other hand, some representatives of both of the two major annelid clades show very limited tissue regeneration and are completely incapable of segmental regeneration. Here we review experimental and descriptive data on annelid regeneration, obtained at different levels of organization, from data on organs and tissues to intracellular and transcriptomic data. Understanding the variety of the cellular and molecular basis of regeneration in annelids can help one to address important questions about the role of stem/dedifferentiated cells and “molecular morphallaxis” in annelid regeneration as well as the evolution of regeneration in general.

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