scholarly journals The Effect of a Fast-Releasing Hydrogen Sulfide Donor on Vascularization of Subcutaneous Scaffolds in Immunocompetent and Immunocompromised Mice

Biomolecules ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 722 ◽  
Author(s):  
Alexandra M. Smink ◽  
Avid Najdahmadi ◽  
Michael Alexander ◽  
Shiri Li ◽  
Samuel Rodriquez ◽  
...  

Islet transplantation into subcutaneous polymer scaffolds has shown to successfully induce normoglycemia in type 1 diabetes models. Vascularization of these scaffolds is imperative for optimal control of glucose levels. We studied the effect of the vascular stimulator hydrogen sulfide (H2S) on the degree of vascularization of a scaffold and the role of the immune system in this process. Scaffolds were subcutaneously implanted in immunocompetent C57BL/6 and immunocompromised nude mice. Mice received twice-daily intraperitoneal injections of the fast-releasing H2S donor sodium hydrosulfide (NaHS, 25 or 50 μmol/kg) or saline for 28 days. After 63 days the vascular network was analyzed by histology and gene expression. Here we showed that the vascularization of a subcutaneous scaffold in nude mice was significantly impaired by H2S treatment. Both the CD31 gene and protein expression were reduced in these scaffolds compared to the saline-treated controls. In C57BL/6 mice, the opposite was found, the vascularization of the scaffold was significantly increased by H2S. The mRNA expression of the angiogenesis marker CD105 was significantly increased compared to the controls as well as the number of CD31 positive blood vessels. In conclusion, the immune system plays an important role in the H2S mediated effect on vascularization of subcutaneous scaffolds.

2021 ◽  
Vol 5 (7) ◽  
pp. 01-04
Author(s):  
Vida Tajiknia ◽  
Maryam Ghandali ◽  
Ardavan Ahmadvand ◽  
Ali Afrasiabi ◽  
Reza Pirdehghan ◽  
...  

Since the first month of this new pandemic situation, all around the world healthcare system has been facing different challenges and difficulties; patients with chronic diseases such as cancer or diabetes with impaired immune system were at greater risk of infections and complications. It goes without saying that this issue was extremely important among pediatric clinicians dealing with diabetic pediatrics. Diabetes is the number one chronic illness among pediatric patients and the most dangerous and frightened complication of it is Diabetic Ketoacidosis (DKA). Studies have shown a strong association between pandemic and increase in new diabetes type 1 cases and its lethal complication called DKA. Here we are going to take a look at existing data and report about cases with this condition trying to find the missing piece of a big puzzle; what is the role of Covid-19 in causing Diabetes in previously healthy kids and what is the real association between SARS-COV2 virus infection and DKA? We are going to review different studies, possible mechanism, new t1dm cases and old cases, with or without covid infection, DKA cases and its severity.


2021 ◽  
Author(s):  
Bhuvaneshwari Sampath ◽  
Priyadarshan Kathirvelu ◽  
Kavitha Sankaranarayanan

The role of immune system in our body is to defense against the foreign bodies. However, if the immune system fails to recognize self and non-self-cells in our body leads to autoimmune diseases. Widespread autoimmune diseases are rheumatoid arthritis, systemic lupus erythematosus, multiple sclerosis, type 1 diabetes, and more yet to be added to the list. This chapter discusses about how stem cell-based therapies and advancement of regenerative medicine endow with novel treatment for autoimmune diseases. Furthermore, in detail, specific types of stem cells and their therapeutic approach for each autoimmune condition along with their efficiency to obtain desired results are discussed. Ultimately, this chapter describes the recent trends in treating autoimmune diseases effectively using advanced stem cell research.


Antioxidants ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 917
Author(s):  
Emma Mitidieri ◽  
Domenico Vanacore ◽  
Carlotta Turnaturi ◽  
Raffaella Sorrentino ◽  
Roberta d’Emmanuele di Villa Bianca

It is well-known that the physiological uterine peristalsis, related to several phases of reproductive functions, plays a pivotal role in fertility and female reproductive health. Here, we have addressed the role of hydrogen sulfide (H2S) signaling in changes of uterine contractions driven by diabetes in non-obese diabetic (NOD) mice, a murine model of type-1 diabetes mellitus. The isolated uterus of NOD mice showed a significant reduction in spontaneous motility coupled to a generalized hypo-contractility to uterotonic agents. The levels of cyclic nucleotides, cAMP and cGMP, notoriously involved in the regulation of uterus homeostasis, were significantly elevated in NOD mouse uteri. This increase was well-correlated with the higher levels of H2S, a non-specific endogenous inhibitor of phosphodiesterases. The exposure of isolated uterus to L-cysteine (L-Cys), but not to sodium hydrogen sulfide, the exogenous source of H2S, showed a weak tocolytic effect in the uterus of NOD mice. Western blot analysis revealed a reorganization of the enzymatic expression with an upregulation of 3-mercaptopyruvate-sulfurtransferase (3-MST) coupled to a reduction in both cystathionine-β-synthase (CBS) and cystathionine-γ-lyase (CSE) expression. In conclusion, the increased levels of cyclic nucleotides dysregulate the uterus peristalsis and contractility in diabetic mice through an increase in basal H2S synthesis suggesting a role of 3-MST.


2010 ◽  
Vol 299 (5) ◽  
pp. H1554-H1567 ◽  
Author(s):  
Mozow Y. Zuidema ◽  
Yan Yang ◽  
Meifang Wang ◽  
Theodore Kalogeris ◽  
Yajun Liu ◽  
...  

The objectives of this study were to determine the role of calcium-activated, small (SK), intermediate (IK), and large (BK) conductance potassium channels in initiating the development of an anti-inflammatory phenotype elicited by preconditioning with an exogenous hydrogen sulfide (H2S) donor, sodium hydrosulfide (NaHS). Intravital microscopy was used to visualize rolling and firmly adherent leukocytes in vessels of the small intestine of mice preconditioned with NaHS (in the absence and presence of SK, IK, and BK channel inhibitors, apamin, TRAM-34, and paxilline, respectively) or SK/IK (NS-309) or BK channel activators (NS-1619) 24 h before ischemia-reperfusion (I/R). I/R induced marked increases in leukocyte rolling and adhesion, effects that were largely abolished by preconditioning with NaHS, NS-309, or NS-1619. The postischemic anti-inflammatory effects of NaHS-induced preconditioning were mitigated by BKB channel inhibitor treatment coincident with NaHS, but not by apamin or TRAM-34, 24 h before I/R. Confocal imaging and immunohistochemistry were used to demonstrate the presence of BKα subunit staining in both endothelial and vascular smooth muscle cells of isolated, pressurized mesenteric venules. Using patch-clamp techniques, we found that BK channels in cultured endothelial cells were activated after exposure to NaHS. Bath application of the same concentration of NaHS used in preconditioning protocols led to a rapid increase in a whole cell K+ current; specifically, the component of K+ current blocked by the selective BK channel antagonist iberiotoxin. The activation of BK current by NaHS could also be demonstrated in single channel recording mode where it was independent of a change in intracellular Ca+ concentration. Our data are consistent with the concept that H2S induces the development of an anti-adhesive state in I/R in part mediated by a BK channel-dependent mechanism.


1999 ◽  
Vol 68 (5) ◽  
pp. 1756-1760 ◽  
Author(s):  
Eric S Lambright ◽  
David J Caparrelli ◽  
Abbas E Abbas ◽  
Takane Toyoizumi ◽  
George Coukos ◽  
...  

2016 ◽  
Vol 46 (10) ◽  
pp. 1743-1749 ◽  
Author(s):  
Jin Feng Chen ◽  
Chan Jiao

ABSTRACT: As a gas signaling molecule, endogenous hydrogen sulfide (H2S) plays a crucial role in the plant stress response. However, the role of H2S in the response to organic pollutants specifically has not been studied. Here, the effects of H2S addition on soybean (Glycine max) seedlings tolerance of 1,4-dichlorobenzene (1,4-DCB) were investigated. Under 1,4-DCB stress, the growth of soybean seedlings roots and stems was inhibited, while L-/D-cysteine desulfhydrase (LCD/DCD) activity was induced and endogenous H2S increased. When applied jointly with sodium hydrosulfide (NaHS), a H2S donor, root growth inhibition was effectively alleviated. Pre-treatment of seedlings with 0.4mmol L-1 NaHS reduced the malondialdehyde (MDA) and reactived oxygen species (ROS) content, mitigating root cell toxicity significantly. Further experiments confirmed that NaHS enhanced soybean seedlings peroxidase (POD) and superoxide dismutase (SOD) enzyme activities. In contrast, these effects were reversed by hypotaurine (HT), a H2S scavenger. Therefore, H2S alleviated 1,4-DCB toxicity in soybean seedlings by regulating antioxidant enzyme activity to reduce cell oxidative damage.


2021 ◽  
Vol 2021 ◽  
pp. 1-6
Author(s):  
Owen Ngalamika ◽  
Wencilaus M. P. Selvaraj ◽  
Fatima K. Yikona ◽  
Chibamba Mumba

Acrodermatitis enteropathica (AE) is a rare disorder arising from inherited or acquired zinc deficiency. It is mainly characterized by acral dermatitis, periorificial dermatitis, alopecia, and gastrointestinal symptoms in the form of diarrhea. There are many complications of AE including local and systemic infections that may develop as a result of untreated AE. In addition, due to the role of zinc in glucose metabolism, chronic zinc deficiency may pose a challenge in the control of blood glucose levels in diabetics. We report the case of a 28-year-old male with type 1 diabetes who presented with signs and symptoms of AE.


Author(s):  
Hannah L. M. Spencer ◽  
Steven D. Shnyder ◽  
Paul M. Loadman ◽  
Robert A. Falconer

The dysregulation of Membrane - type 1 matrix metalloproteinase (MT1-MMP) has been extensively studied in numerous cancer types, and plays key roles in angiogenesis, cancer progression, and metastasis. MT1-MMP is a predictor of poor prognosis in osteosarcoma (OS), yet the molecular mechanisms of disease progression are unclear. This review provides a summary of the literature relating to the gene and protein expression of MT1-MMP (MMP-14) in OS clinical samples, evaluates the expression in cell lines and experimental models, and analyses its potential role in the progression and metastasis of OS. In addition, the therapeutic potential of MT1-MMP as a drug target has been assessed. Due to the biological complexity of MMPs, inhibition has proven to be challenging. However, exploiting the expression and proteolytic capacity of MT1-MMP could open new avenues in the search for novel, safer and selective drugs for use in OS.


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