scholarly journals Adiponectin: a pleiotropic hormone with multifaceted roles

2021 ◽  
Vol 67 (6) ◽  
pp. 98-112
Author(s):  
S. S. Shklyaev ◽  
G. A. Melnichenko ◽  
N. N. Volevodz ◽  
N. A. Falaleeva ◽  
S. A. Ivanov ◽  
...  

Adipose tissue mostly composed of different types of fat is one of the largest endocrine organs in the body playing multiple intricate roles including but not limited to energy storage, metabolic homeostasis, generation of heat, participation in immune functions and secretion of a number of biologically active factors known as adipokines. The most abundant of them is adiponectin. This adipocite-derived hormone exerts pleiotropic actions and exhibits insulin-sensitizing, antidiabetic, anti-obesogenic, anti-inflammatory, antiatherogenic, cardio- and neuroprotective properties. Contrariwise to its protective effects against various pathological events in different cell types, adiponectin may have links to several systemic diseases and malignances. Reduction in adiponectin levels has an implication in COVID-19-associated respiratory failure, which is attributed mainly to a phenomenon called ‘adiponectin paradox’. Ample evidence about multiple functions of adiponectin in the body was obtained from animal, mostly rodent studies. Our succinct review is entirely about multifaceted roles of adiponectin and mechanisms of its action in different physiological and pathological states.

Author(s):  
U. Aebi ◽  
P. Rew ◽  
T.-T. Sun

Various types of intermediate-sized (10-nm) filaments have been found and described in many different cell types during the past few years. Despite the differences in the chemical composition among the different types of filaments, they all yield common structural features: they are usually up to several microns long and have a diameter of 7 to 10 nm; there is evidence that they are made of several 2 to 3.5 nm wide protofilaments which are helically wound around each other; the secondary structure of the polypeptides constituting the filaments is rich in ∞-helix. However a detailed description of their structural organization is lacking to date.


1992 ◽  
Vol 67 (01) ◽  
pp. 154-160 ◽  
Author(s):  
P Meulien ◽  
M Nishino ◽  
C Mazurier ◽  
K Dott ◽  
G Piétu ◽  
...  

SummaryThe cloning of the cDNA encoding von Willebrand factor (vWF) has revealed that it is synthesized as a large precursor (pre-pro-vWF) molecule and it is now clear that the prosequence or vWAgll is responsible for the intracellular multimerization of vWF. We have cloned the complete vWF cDNA and expressed it using a recombinant vaccinia virus as vector. We have characterized the structure and function of the recombinant vWF (rvWF) secreted from five different cell types: baby hamster kidney (BHK), Chinese hamster ovary (CHO), human fibroblasts (143B), mouse fibroblasts (L) and primary embryonic chicken cells. Forty-eight hours after infection, the quantity of vWF antigen found in the cell supernatant varied from 3 to 12 U/dl depending on the cell type. By SDS-agarose gel electrophoresis, the percentage of high molecular weight forms of vWF varied from 39 to 49% relative to normal plasma for BHK, CHO, 143B and chicken cells but was less than 10% for L cells. In all cell types, the two anodic subbands of each multimer were missing. The two cathodic subbands were easily detected only in BHK and L cells. By SDS-PAGE of reduced samples, pro-vWF was present in similar quantity to the fully processed vWF subunit in L cells, present in moderate amounts in BHK and CHO and in very low amounts in 143B and chicken cells. rvWF from all cells bound to collagen and to platelets in the presence of ristocetin, the latter showing a high correlation between binding efficiency and degree of multimerization. rvWF from all cells was also shown to bind to purified FVIII and in this case binding appeared to be independent of the degree of multimerization. We conclude that whereas vWF is naturally synthesized only by endothelial cells and megakaryocytes, it can be expressed in a biologically active form from various other cell types.


2020 ◽  
Author(s):  
Huixia Ren ◽  
Yanjun Li ◽  
Chengsheng Han ◽  
Yi Yu ◽  
Bowen Shi ◽  
...  

ABSTRACTThe Ca2+ modulated pulsatile secretions of glucagon and insulin by pancreatic α and β cells play a key role in glucose metabolism and homeostasis. However, how different types of islet cells couple and coordinate via paracrine interactions to produce various Ca2+ oscillation patterns are still elusive. By designing a microfluidic device to facilitate long-term recording of islet Ca2+ activity at single cell level and simultaneously identifying different cell types in live islet imaging, we show heterogeneous but intrinsic Ca2+ oscillation patterns of islets upon glucose stimulation. The α and β cells oscillate in antiphase and are globally phase locked to various phase delays, causing fast, slow or mixed oscillations. A mathematical model of coupled phase oscillators quantitatively agrees with experiments and reveals the essential role of paracrine regulations in tuning the oscillation modes. Our study highlights the importance of cell-cell interactions to generate stable but tunable islet oscillation patterns.


mBio ◽  
2021 ◽  
Vol 12 (5) ◽  
Author(s):  
Jing Liu ◽  
Adam Vanarsdall ◽  
Dong-Hua Chen ◽  
Andrea Chin ◽  
David Johnson ◽  
...  

HCMV is a herpesvirus that infects a large percentage of the adult population and causes significant levels of disease in immunocompromised individuals and birth defects in the developing fetus. The virus encodes a complex protein machinery that coordinates infection of different cell types in the body, including a trimer formed of gH, gL, and gO subunits.


‘Infection and immunity’ considers the response of the body to pathogens, such as bacteria, viruses, prions, fungi, and parasites, which are discussed in terms of their nature, life cycle, and modes of infection. The role of the immune system in defence against infection is discussed, including innate and adaptive (acquired) immunity, antigens, the major histocompatibility complex, and the different cell types involved (antigen-presenting cells, T-cells, and B-cells). The mechanisms and cellular basis of inflammation are considered, as are post-infection repair mechanisms, and pathologies of the immune system such as hypersensitivity, autoimmunity and transplantations, and immunodeficiency (both primary and secondary to other diseases).


Author(s):  
Christian J. Hendriksz ◽  
Francois Karstens

There are 8 different types of diseases of the mucopolysaccharides, each caused by a deficiency in one of 10 different enzymes involved in the degradation of glycosaminoglycans (GAGs). Partially degraded GAGs accumulate within the lysosomes of many different cell types and lead to clinical symptoms and excretion of large amounts of GAGs in the urine. Heritability is autosomal recessive except for MPS type II, which is X-linked. The disorders are chronic and progressive and, although the specific types all have their individual features, they share an abundance of clinical similarities. All involve the musculoskeletal, the cardiovascular, the pulmonary and the central nervous system.


2018 ◽  
Vol 62 (2) ◽  
pp. 193-204 ◽  
Author(s):  
Adam J. Poe ◽  
Anne A. Knowlton

Exosomes have become an important player in intercellular signaling. These lipid microvesicles can stably transfer miRNA, protein, and other molecules between cells and circulate throughout the body. Exosomes are released by almost all cell types and are present in most if not all biological fluids. The biologically active cargo carried by exosomes can alter the phenotype of recipient cells. Exosomes increasingly are recognized as having an important role in the progression and treatment of cardiac disease states. Injured cardiac cells can release exosomes with important pathological effects on surrounding tissue, in addition to effecting other organs. But of equal interest is the possible benefit(s) conferred by exosomes released from stem cells for use in treatment and possible repair of cardiac damage.


2020 ◽  
Author(s):  
Sabin Bhandari ◽  
Ruomei Li ◽  
Jaione Simón-Santamaría ◽  
Peter McCourt ◽  
Steinar Daae Johansen ◽  
...  

Abstract Background: Liver sinusoidal endothelial cells (LSECs) and Kupffer cells (KCs; liver resident macrophages) form the body´s most effective scavenger cell system for the removal of harmful blood-borne substances, ranging from modified self-proteins to pathogens and xenobiotics. Controversies in the literature regarding the LSEC phenotype pose a challenge when determining distinct functionalities of KCs and LSECs. This may be due to overlapping functions of the two cells, insufficient purification and/or identification of the cells, rapid dedifferentiation of LSECs in vitro, or species differences. We therefore characterized and quantitatively compared expressed gene products of freshly isolated, highly pure LSECs (fenestrated SE-1/FcgRIIb2+) and KCs (CD11b/c+) from Sprague Dawley, Crl:CD(SD), male rats using high throughput mRNA-sequencing and label-free proteomics.Results: We observed a robust correlation between the proteomes and transcriptomes of the two cell types. Integrative analysis of the global molecular profile demonstrated the immunological aspects of LSECs. The constitutive expression of several immune genes and corresponding proteins of LSECs bore some resemblance with the expression in macrophages. LSECs and KCs both expressed high levels of scavenger receptors (SR) and C-type lectins. Equivalent expression of SR-A1 (Msr1), mannose receptor (Mrc1), SR-B1 (Scarb1), and SR-B3 (Scarb2) suggested functional similarity between the two cell types, while functional distinction between the cells was evidenced by LSEC-specific expression of the SRs stabilin-1 (Stab1) and stabilin-2 (Stab2), and the C-type lectins LSECtin (Clec4g) and DC-SIGNR (Clec4m). Many immune regulatory factors were differentially expressed in LSECs and KCs, with one cell predominantly expressing a specific cytokine/chemokine and the other cell the cognate receptor, illustrating the complex cytokine milieu of the sinusoids. Both cells expressed genes and proteins involved in antigen processing and presentation, and lymphocyte co-stimulation. Conclusions: Our findings support complementary and partly overlapping scavenging and immune functions of LSECs and KCs. This highlights the importance of including LSECs in studies of liver immunity, and liver clearance and toxicity of large molecule drugs and nano-formulations.


2021 ◽  
Author(s):  
Hui Cai ◽  
Dezhe Qin ◽  
Sha Peng

To facilitate temperature adjustments, the testicles are located outside the body cavity. In most mammals, the temperature of the testes is lower than the body temperature to ensure the normal progression of spermatogenesis. Rising temperatures affect spermatogenesis and eventually lead to a decline in male fertility or even infertility. However, the testes are composed of different cell types, including spermatogonial stem cells, spermatocytes, spermatozoa, Leydig cells, and Sertoli cells, which have different cellular responses to heat stress. Recent studies have shown that using different drugs can relieve heat-stress-induced reproductive damage by regulating different signaling pathways. Here, we review the mechanisms by which heat stress damages different cells in testes and possible treatments.


2015 ◽  
Vol 6 (2) ◽  
pp. 96-108
Author(s):  
Elena Aleksandrovna Dementeva ◽  
Olga Petrovna Gurina

The key immunology problem remains the understanding of the mechanisms for the effective protection of the body against various pathogens with simultaneous suppression of the immune response to autoantigens. The pathogenesis of neoplastic pathological processes includes violations of the mechanisms of normal cell growth and cell proliferation. Antitumor immune response is a complex event, involving many different cell types. But despite the ability of the immune system to recognize and respond to a variety of tumor-associated antigens, the neoplastic process overcomes the protective forces of the organism, grows and spreads. For cancer cells characterized by independence from antiproliferative signals, autocrine stimulation of growth disturbances in the system, induction of apoptosis and control of genome stability. As a result of accumulation of genetic and epigenetic changes in tumor cells differ significantly from the normal range and the level of expression of genes involved in the transformation process, the accumulation of mutations in key genes promoters and suppressors of tumorigenesis. This creates the opportunity for recognition by cells of the immune system. The study of changes in value and operation of the various elements of the immune system in the development of experimental neoplastic process allows you to identify the mechanisms of interaction in the system «malignant tumor-immune system, to assess patterns of interaction with other organs and tissues, to create a theoretical pathogenetically reasonable premise for the development of anticancer therapy.


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