Relating Lymphatic Vessel Mechanical Properties Measured in Vitro to Regulation of Interstitial Fluid Volume in Vivo

AbstractCurrent materials used in biomedical devices do not match tissue’s mechanical properties and leach various chemicals into the body. These deficiencies pose significant health risks that are further exacerbated by invasive implantation procedures. Herein, we leverage the brush-like polymer architecture to design and administer minimally invasive injectable elastomers that cure in vivo into leachable-free implants with mechanical properties matching the surrounding tissue. This strategy allows tuning curing time from minutes to hours, which empowers a broad range of biomedical applications from rapid wound sealing to time-intensive reconstructive surgery. These injectable elastomers support in vitro cell proliferation, while also demonstrating in vivo implant integrity with a mild inflammatory response and minimal fibrotic encapsulation.

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Zn-Containing Membranes for Guided Bone Regeneration in Dentistry

Polymers ◽

10.3390/polym13111797 ◽

2021 ◽

Vol 13 (11) ◽

pp. 1797

Author(s):

Manuel Toledano ◽

Marta Vallecillo-Rivas ◽

María T. Osorio ◽

Esther Muñoz-Soto ◽

Manuel Toledano-Osorio ◽

...

Keyword(s):

Mechanical Properties ◽

Bone Regeneration ◽

Bone Healing ◽

Bone Repair ◽

Complex Modulus ◽

Bacterial Colonization ◽

Guided Bone Regeneration ◽

M2 Macrophage

Barrier membranes are employed in guided bone regeneration (GBR) to facilitate bone in-growth. A bioactive and biomimetic Zn-doped membrane with the ability to participate in bone healing and regeneration is necessary. The aim of the present study is to state the effect of doping the membranes for GBR with zinc compounds in the improvement of bone regeneration. A literature search was conducted using electronic databases, such as PubMed, MEDLINE, DIMDI, Embase, Scopus and Web of Science. A narrative exploratory review was undertaken, focusing on the antibacterial effects, physicochemical and biological properties of Zn-loaded membranes. Bioactivity, bone formation and cytotoxicity were analyzed. Microstructure and mechanical properties of these membranes were also determined. Zn-doped membranes have inhibited in vivo and in vitro bacterial colonization. Zn-alloy and Zn-doped membranes attained good biocompatibility and were found to be non-toxic to cells. The Zn-doped matrices showed feasible mechanical properties, such as flexibility, strength, complex modulus and tan delta. Zn incorporation in polymeric membranes provided the highest regenerative efficiency for bone healing in experimental animals, potentiating osteogenesis, angiogenesis, biological activity and a balanced remodeling. Zn-loaded membranes doped with SiO2 nanoparticles have performed as bioactive modulators provoking an M2 macrophage increase and are a potential biomaterial for promoting bone repair. Zn-doped membranes have promoted pro-healing phenotypes.

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Fibronectin Adsorption on Electrospun Synthetic Vascular Grafts Attracts Endothelial Progenitor Cells and Promotes Endothelialization in Dynamic In Vitro Culture

Cells ◽

10.3390/cells9030778 ◽

2020 ◽

Vol 9 (3) ◽

pp. 778 ◽

Cited By ~ 4

Author(s):

Ruben Daum ◽

Dmitri Visser ◽

Constanze Wild ◽

Larysa Kutuzova ◽

Maria Schneider ◽

...

Keyword(s):

Mechanical Properties ◽

Cell Activation ◽

Vascular Endothelial Cells ◽

Endothelial Progenitor ◽

Advanced Therapy Medicinal Product ◽

Endothelial Colony Forming Cells ◽

Advanced Therapy ◽

Custom Made

Appropriate mechanical properties and fast endothelialization of synthetic grafts are key to ensure long-term functionality of implants. We used a newly developed biostable polyurethane elastomer (TPCU) to engineer electrospun vascular scaffolds with promising mechanical properties (E-modulus: 4.8 ± 0.6 MPa, burst pressure: 3326 ± 78 mmHg), which were biofunctionalized with fibronectin (FN) and decorin (DCN). Neither uncoated nor biofunctionalized TPCU scaffolds induced major adverse immune responses except for minor signs of polymorph nuclear cell activation. The in vivo endothelial progenitor cell homing potential of the biofunctionalized scaffolds was simulated in vitro by attracting endothelial colony-forming cells (ECFCs). Although DCN coating did attract ECFCs in combination with FN (FN + DCN), DCN-coated TPCU scaffolds showed a cell-repellent effect in the absence of FN. In a tissue-engineering approach, the electrospun and biofunctionalized tubular grafts were cultured with primary-isolated vascular endothelial cells in a custom-made bioreactor under dynamic conditions with the aim to engineer an advanced therapy medicinal product. Both FN and FN + DCN functionalization supported the formation of a confluent and functional endothelial layer.

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Atrial Natriuretic Peptide as a Regulator of Transvascular Fluid Balance

Physiology ◽

10.1152/physiologyonline.1996.11.3.138 ◽

1996 ◽

Vol 11 (3) ◽

pp. 138-143 ◽

Cited By ~ 2

Author(s):

EM Renkin ◽

VL Tucker

Keyword(s):

Atrial Natriuretic Peptide ◽

Natriuretic Peptide ◽

Plasma Volume ◽

Fluid Balance ◽

Interstitial Fluid ◽

Fluid Volume ◽

Interstitial Fluid Volume ◽

Atrial Natriuretic

Unlike other natriuretics, which act via the kidneys to reduce interstitial fluid volume with little change in plasma volume, atrial natriuretic peptide has important extrarenal actions that enable it to reduce plasma volume preferentially.

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Evaluation of renal and cardiovascular protection mechanisms of SGLT2 inhibitors: model-based analysis of clinical data

AJP Renal Physiology ◽

10.1152/ajprenal.00202.2018 ◽

2018 ◽

Vol 315 (5) ◽

pp. F1295-F1306 ◽

Cited By ~ 15

Author(s):

K. Melissa Hallow ◽

Peter J. Greasley ◽

Gabriel Helmlinger ◽

Lulu Chu ◽

Hiddo J. Heerspink ◽

...

Keyword(s):

Renal Impairment ◽

Clinical Data ◽

Healthy Subjects ◽

Interstitial Fluid ◽

Sglt2 Inhibitors ◽

Fluid Volume ◽

Diabetic Patients ◽

Pressure Reduction ◽

Physiological Variables ◽

Interstitial Fluid Volume

The mechanisms of cardiovascular and renal protection observed in clinical trials of sodium-glucose cotransporter 2 (SGLT2) inhibitors (SGLT2i) are incompletely understood and likely multifactorial, including natriuretic, diuretic, and antihypertensive effects, glomerular pressure reduction, and lowering of plasma and interstitial fluid volume. To quantitatively evaluate the contribution of proposed SGLT2i mechanisms of action on changes in renal hemodynamics and volume status, we coupled a mathematical model of renal function and volume homeostasis with clinical data in healthy subjects administered 10 mg of dapagliflozin once daily. The minimum set of mechanisms necessary to reproduce observed clinical responses (urinary sodium and water excretion, serum creatinine and sodium) was determined, and important unobserved physiological variables (glomerular pressure, blood and interstitial fluid volume) were then simulated. We further simulated the response to SGLT2i in diabetic virtual patients with and without renal impairment. Multiple mechanisms were required to explain the observed response: 1) direct inhibition of sodium and glucose reabsorption through SGLT2, 2) SGLT2-driven inhibition of Na+/H+ exchanger 3 sodium reabsorption, and 3) osmotic diuresis coupled with peripheral sodium storage. The model also showed that the consequences of these mechanisms include lowering of glomerular pressure, reduction of blood and interstitial fluid volume, and mild blood pressure reduction, in agreement with clinical observations. The simulations suggest that these effects are more significant in diabetic patients than healthy subjects and that while glucose excretion may diminish with renal impairment, improvements in glomerular pressure and blood volume are not diminished at lower glomerular filtration rate, suggesting that cardiorenal benefits of SGLT2i may be sustained in renally impaired patients.

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In Vitro and In Vivo Degradation, Mechanical Properties, and Histocompatibility of Weft-Knitted Silk Mesh-Like Grafts

Journal of Biomaterials and Tissue Engineering ◽

10.1166/jbt.2022.2911 ◽

2022 ◽

Vol 12 (2) ◽

pp. 411-416

Author(s):

Liang Tang ◽

Si-Yu Zhao ◽

Ya-Dong Yang ◽

Geng Yang ◽

Wen-Yuan Zhang ◽

...

Keyword(s):

Mechanical Properties ◽

Simulated Body Fluid ◽

Body Fluid ◽

Degradation Rate ◽

Maximum Load ◽

Artificial Ligament ◽

In Vivo Degradation

To investigate the degradation, mechanical properties, and histocompatibility of weft-knitted silk mesh-like grafts, we carried out the In Vitro and In Vivo silk grafts degradation assay. The In Vitro degradation experiment was performed by immersing the silk grafts in simulated body fluid for 1 year, and the results showed that the degradation rate of the silk mesh-like grafts was very slow, and there were few changes in the mechanical properties and quality of the silk mesh-like graft. In Vivo degradation assay was taken by implantation of the silk mesh-like grafts into the subcutaneous muscles of rabbits. At 3, 6, and 12 months postoperation, the rate of mass loss was 19.36%, 31.84%, and 58.77%, respectively, and the maximum load was 63.85%, 34.63%, and 10.76%, respectively of that prior to degradation. The results showed that the degradation rate of the silk graft and the loss of mechanical properties In Vivo were faster than the results obtained in the In Vitro experiments. In addition, there were no significant differences in secretion of serum IL-6 and TNF-α between the experimental and normal rabbits (P >0.05), suggesting no obvious inflammatory reaction. The findings suggest that the weft-knitted silk mesh-like grafts have good mechanical properties, histocompatibility, and In Vivo degradation rate, and therefore represent a candidate material for artificial ligament

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Interstitial fluid volume: local regulatory mechanisms.

Physiological Reviews ◽

10.1152/physrev.1981.61.3.556 ◽

1981 ◽

Vol 61 (3) ◽

pp. 556-643 ◽

Cited By ~ 276

Author(s):

K Aukland ◽

G Nicolaysen

Keyword(s):

Interstitial Fluid ◽

Fluid Volume ◽

Regulatory Mechanisms ◽

Interstitial Fluid Volume

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Effects of Cyclic Stress on the Mechanical Properties of Cultured Collagen Fascicles from the Rabbit Patellar Tendon

Journal of Biomechanical Engineering ◽

10.1115/1.1634286 ◽

2003 ◽

Vol 125 (6) ◽

pp. 893-901 ◽

Cited By ~ 21

Author(s):

Ei Yamamoto ◽

Susumu Tokura ◽

Kozaburo Hayashi

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Patellar Tendon ◽

Control Level ◽

Quadratic Function ◽

Peak Stress ◽

Cyclic Stress ◽

Original Strength

Effects of cyclic stress on the mechanical properties of collagen fascicles were studied by in vitro tissue culture experiments. Collagen fascicles (approximately 300 μm in diameter) obtained from the rabbit patellar tendon were applied cyclic load at 4 Hz for one hour per day during culture period for one or two weeks, and then their mechanical properties were determined using a micro-tensile tester. There was a statistically significant correlation between tensile strength and applied peak stress in the range of 0 to 5 MPa, and the relation was expressed by a quadratic function. The maximum strength (19.4 MPa) was obtained at the applied peak stress of 1.8 MPa. The tensile strength of fascicles were within a range of control values, if they were cultured under peak stresses between 1.1 and 2.6 MPa. Similar results were also observed in the tangent modulus, which was maintained at control level under applied peak stresses between 0.9 and 2.8 MPa. The stress of 0.9 to 1.1 MPa is equivalent to approximately 40% of the in vivo peak stress which is developed in the intact rabbit patellar tendon by running, whereas that of 2.6 to 2.8 MPa corresponds to approximately 120% of the in vivo peak stress. Therefore, the fascicles cultured under applied peak stresses of lower than 40% and higher than 120% of the in vivo peak stress do not keep the original strength and modulus. These results indicate that the mechanical properties of cultured collagen fascicles strongly depend upon the magnitude of the stress applied during culture, which are similar to our previous results observed in stress-shielded and overstressed patellar tendons in vivo.

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Injectable Non-leaching Tissue-mimetic Bottlebrush Elastomers: A New Platform for Advancing Reconstructive Surgery

10.21203/rs.3.rs-100872/v1 ◽

2020 ◽

Author(s):

Erfan Dashtimoghadam ◽

Farahnaz Fahimipour ◽

Andrew Keith ◽

Foad Vashahi ◽

Pavel Popryadukhin ◽

...

Keyword(s):

Mechanical Properties ◽

Reconstructive Surgery ◽

Biomedical Applications ◽

The Body ◽

Surrounding Tissue ◽

Curing Time ◽

Materials Used ◽

Significant Health

Abstract Current materials used in biomedical devices do not match tissue’s mechanical properties and leach various chemicals into the body. These deficiencies pose significant health risks that are further exacerbated by invasive implantation procedures. Herein, we leverage the brush-like polymer architecture to design and administer minimally invasive injectable elastomers that cure in vivo into leachable-free implants with mechanical properties matching the surrounding tissue. This strategy allows tuning curing time from minutes to hours, which empowers a broad range of biomedical applications from rapid wound sealing to time-intensive reconstructive surgery. These injectable elastomers support in vitro cell proliferation, while also demonstrating in vivo implant integrity with a mild inflammatory response and minimal fibrotic encapsulation.

Download Full-text