Proteomic Analysis Reveals the Contribution of TGFβ/Smad4 Signaling Pathway to Cell Differentiation During Planarian Tail Regeneration

Mining differentially expressed genes during paratomy in the transcriptome of the flatworm Stenostomum leucops

Paratomy is an asexual reproductive process that occurs in annelids, flatworms and other groups. During this process, anterior structures are formed in the middle of the body, giving rise to segmented organisms, each segment being called a zooid. Once formed, the zooids detach and form new organisms. Using RNAseq of worms prior to zooid formation and with two zooids, we search for genes that are differentially expressed and may be related to the control of this process in the flatworm Stenostomum leucops. Several signaling pathways showed differential expression, including MAPK/ERK, PI3K-Akt, Wnt, TGFb, mTOR, FoxO and others. Forty-five genes were found to be particularly significant because they are differentially expressed and play an important role in the development of other flatworms. These include ERK, MKP, JNK, PI3K, PTEN, β -catenin, FoxO, Sufu, GH and others. The results suggest some similarities in gene regulation between paratomy and regeneration observed in other flatworms after fission or amputation. In worms without zooids, pathways required for cell proliferation, differentiation of cells into multiple cell lineages and determination of the body axis are activated. In worms with 2 zooids, genes involved in cell growth and apoptosis are activated. Activation of genes involved in neoblast proliferation and maintenance appears to occur at both stages.

Nephrotoxicity Induced by Cisplatin Intake in Experimental Rats and Therapeutic Approach of Using Mesenchymal Stem Cells and Spironolactone

Chronic kidney disease may lead to subsequent tissue fibrosis. However, many factors can combat injurious stimuli in these tissues aiming to repair, heal, and alleviate any disturbance. Chemokines release, migration of inflammatory cells to the affected site, and activation of fibroblasts for the production of extracellular matrix are commonly observed in this disease. In the last years, many studies have focused on spironolactone (SPL), a mineralocorticoid receptor antagonist, and its pharmacological effects. In the present study, SPL was selected as an anti-inflammatory agent to combat nephrotoxicity and renal fibrosis induced by cisplatin. Mesenchymal stem cells (MSCs) were also selected in addition as a referring agent. Renal fibrosis induced by cisplatin intake significantly increased creatinine, urea, nuclear factor kappa B, insulin-like growth factor-1, fibroblast growth factor-23, and kidney malondialdehyde (MDA) content. Hepatocyte growth factor and renal content of reduced glutathione demonstrated a significant decrease. Histopathological examination of kidney tissues demonstrated marked cellular changes which are correlated with the biochemical results. Oral SPL intake (20 mg/kg/body weight) daily for 4 weeks and MSCs administration (3 × 106 cell/rat) intravenous to the experimental rats resulted in a significant improvement of both the biomarkers studied and the histopathological profile of the renal tissue. Individual administration of spironolactone and MSCs exhibited a marked anti-inflammatory potential and alleviated to a great extent the nephrotoxicity and renal fibrotic pattern induced by cisplatin.