Acid- and Volume-Sensitive Chloride Currents in Human Chondrocytes

Autosomal dominant polycystic kidney disease (ADPKD) is caused by loss of function of PKD1 (polycystin 1) or PKD2 (polycystin 2). The Ca2+-activated Cl− channel TMEM16A has a central role in ADPKD. Expression and function of TMEM16A is upregulated in ADPKD which causes enhanced intracellular Ca2+ signaling, cell proliferation, and ion secretion. We analyzed kidneys from Pkd1 knockout mice and found a more pronounced phenotype in males compared to females, despite similar levels of expression for renal tubular TMEM16A. Cell proliferation, which is known to be enhanced with loss of Pkd1−/−, was larger in male when compared to female Pkd1−/− cells. This was paralleled by higher basal intracellular Ca2+ concentrations in primary renal epithelial cells isolated from Pkd1−/− males. The results suggest enhanced intracellular Ca2+ levels contributing to augmented cell proliferation and cyst development in male kidneys. Enhanced resting Ca2+ also caused larger basal chloride currents in male primary cells, as detected in patch clamp recordings. Incubation of mouse primary cells, mCCDcl1 collecting duct cells or M1 collecting duct cells with dihydrotestosterone (DHT) enhanced basal Ca2+ levels and increased basal and ATP-stimulated TMEM16A chloride currents. Taken together, the more severe cystic phenotype in males is likely to be caused by enhanced cell proliferation, possibly due to enhanced basal and ATP-induced intracellular Ca2+ levels, leading to enhanced TMEM16A currents. Augmented Ca2+ signaling is possibly due to enhanced expression of Ca2+ transporting/regulating proteins.

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Initial phase I safety of retrovirally transduced human chondrocytes expressing transforming growth factor-beta-1 in degenerative arthritis patients

Cytotherapy ◽

10.3109/14653249.2011.629645 ◽

2012 ◽

Vol 14 (2) ◽

pp. 247-256 ◽

Cited By ~ 79

Author(s):

Chul-Won Ha ◽

Moon Jong Noh ◽

Kyoung Baek Choi ◽

Kwan Hee Lee

Keyword(s):

Growth Factor ◽

Phase I ◽

Transforming Growth Factor Beta ◽

Initial Phase ◽

Transforming Growth Factor ◽

Human Chondrocytes ◽

Degenerative Arthritis ◽

Growth Factor Beta

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Reversal of senescence-associated beta-galactosidase expression during in vitro three-dimensional tissue-engineering of human chondrocytes in a polymer scaffold

Scientific Reports ◽

10.1038/s41598-021-93607-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Shojiro Katoh ◽

Atsuki Fujimaru ◽

Masaru Iwasaki ◽

Hiroshi Yoshioka ◽

Rajappa Senthilkumar ◽

...

Keyword(s):

Regenerative Medicine ◽

Replicative Senescence ◽

Cultured Cells ◽

Three Dimensional ◽

Human Chondrocytes ◽

Cartilage Tissue ◽

Optimal Method ◽

Beta Galactosidase

AbstractRegenerative medicine applications require cells that are not inflicted with senescence after in vitro culture for an optimal in vivo outcome. Methods to overcome replicative senescence include genomic modifications which have their own disadvantages. We have evaluated a three-dimensional (3D) thermo-reversible gelation polymer (TGP) matrix environment for its capabilities to reverse cellular senescence. The expression of senescence-associated beta-galactosidase (SA-βgal) by human chondrocytes from osteoarthritis-affected cartilage tissue, grown in a conventional two-dimensional (2D) monolayer culture versus in 3D-TGP were compared. In 2D, the cells de-differentiated into fibroblasts, expressed higher SA-βgal and started degenerating at 25 days. SA-βgal levels decreased when the chondrocytes were transferred from the 2D to the 3D-TGP culture, with cells exhibiting a tissue-like growth until 42–45 days. Other senescence associated markers such as p16INK4a and p21 were also expressed only in 2D cultured cells but not in 3D-TGP tissue engineered cartilage. This is a first-of-its-kind report of a chemically synthesized and reproducible in vitro environment yielding an advantageous reversal of aging of human chondrocytes without any genomic modifications. The method is worth consideration as an optimal method for growing cells for regenerative medicine applications.

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Basal chloride currents in murine airway epithelial cells: modulation by CFTR

AJP Cell Physiology ◽

10.1152/ajpcell.1998.274.4.c904 ◽

1998 ◽

Vol 274 (4) ◽

pp. C904-C913 ◽

Cited By ~ 21

Author(s):

R. Tarran ◽

M. A. Gray ◽

M. J. Evans ◽

W. H. Colledge ◽

R. Ratcliff ◽

...

Keyword(s):

Cystic Fibrosis ◽

Airway Epithelial Cells ◽

Transmembrane Conductance Regulator ◽

Airway Epithelial ◽

Wild Type ◽

Patch Clamp Technique ◽

Chloride Currents ◽

Cation Permeability ◽

Current Voltage ◽

Respiratory Cells

We have isolated ciliated respiratory cells from the nasal epithelium of wild-type and cystic fibrosis (CF) null mice and used the patch-clamp technique to investigate their basal conductances. Current-clamp experiments on unstimulated cells indicated the presence of K+ and Cl− conductances and, under certain conditions, a small Na+conductance. Voltage-clamp experiments revealed three distinct Cl− conductances. I tv-indep was time and voltage independent with a linear current-voltage ( I- V) plot; I v-actexhibited activation at potentials greater than ±50 mV, giving an S-shaped I- Vplot; and I hyp-act was activated by hyperpolarizing potentials and had an inwardly rectified I- Vplot. The current density sequence was I hyp-act = I v-act ≫ I tv-indep. These conductances had Cl−-to- N-methyl-d-glucamine cation permeability ratios of between 2.8 and 10.3 and were unaffected by tamoxifen, flufenamate, glibenclamide, DIDS, and 5-nitro-2-(3-phenylpropylamino) benzoic acid but were inhibited by Zn2+ and Gd3+. I tv-indep and I v-act were present in wild-type and CF cells at equal density and frequency. However, I hyp-actwas detected in only 3% of CF cells compared with 26% of wild-type cells, suggesting that this conductance may be modulated by cystic fibrosis transmembrane conductance regulator (CFTR).

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Primary human chondrocytes respond to compression with phosphoproteomic signatures that include microtubule activation

Journal of Biomechanics ◽

10.1016/j.jbiomech.2019.109367 ◽

2019 ◽

Vol 97 ◽

pp. 109367 ◽

Cited By ~ 1

Author(s):

Donald L. Zignego ◽

Jonathan K. Hilmer ◽

Brian Bothner ◽

William J. Schell ◽

Ronald K. June

Keyword(s):

Human Chondrocytes

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