MicroRNA-301a attenuates collagen gel contractility and promotes proliferation of human bone marrow derived mesenchymal stem cells
Bibliographic record
Abstract
Previous data in our lab suggests that human mesenchymal stem cells (MSCs) of bone marrow origin display a myofibroblast phenotype in vitro. Coincident with the onset of a myofibroblast phenotype, we observed a reduction in miR-301a expression. We hypothesized that miR-301a may govern the differentiation of bone marrow derived MSCs to myofibroblasts. MSCs were isolated from the sternum of patients undergoing open heart surgery and transfected with premiR-301a at early passage. We analyzed contractility through plating on flexible collagen gels and cell proliferation. Western blot and qRT-PCR were used to determine mRNA and protein expression of myosin isoforms and myofibroblast markers. Human MSCs were found to express non-muscle myosin (NMM)-IIA and -IIB, other myofibroblast markers such as α-smooth muscle actin (SMA), vimentin, FSP-1, ED-A Fibronectin, and procollagen I and contracted collagen gels in the basal state. Cells cultured in serum rich conditions displayed decreased contractility and increased proliferation whereas cells cultured in serum free conditions showed increased contractility and decreased proliferative capacity. The proliferative phenotype was associated with increased mRNA expression of miR-301a host gene, ska2. Overexpression of miR-301a caused a reduction in collagen gel contraction and an increase in proliferation when compared with a negative-scramble control. This was associated with decreased NMM-IIA and IIB mRNA. Western blot analysis confirmed decreased levels of NMM-IIA and IIB in addition to decreased protein expression of α-SMA, ED-A Fibronectin and procollagen I. In conclusion, MSCs display a dichotomous proliferative versus contractile phenotype in vitro. Our results suggest that miR-301a plays a mechanistic role in this dichotomy, such that it suppresses the myofibroblastic, contractile phenotype.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 0.001 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".