Allelic Imbalance of mRNA Associated with α2-HS Glycoprotein (Fetuin-A) Polymorphism

Matrix regeneration proteins in the hypoxia-triggered exosomes of shoulder tenocytes and adipose-derived mesenchymal stem cells

Regenerative functions of exosomes rely on their contents which are influenced by pathological stimuli, including hypoxia, in rotator cuff tendon injuries (RCTI). The hypoxic environment triggers tenocytes and adjacent adipose-derived mesenchymal stem cells (ADMSCs) to release regenerative mediators to the ECM via the exosomes which elicit autocrine/paracrine responses to protect the tendon matrix from injury. We investigated the exosomal protein contents from tenocytes and subcutaneous ADMSCs from the shoulder of Yucatan microswine cultured under hypoxic conditions (2% O₂). The exosomal proteins were detected using high-resolution mass spectrometry nano-LC-MS/MS Tribrid system and were compiled using 'Scaffold' software. Hypoxic exosomes from tenocytes and ADMSCs carried 199 and 65 proteins, respectively. The key proteins identified by mass spectrometry and associated with ECM homeostasis from hypoxic ADMSCs included MMP2, COL6A, CTSD and TN-C and those from hypoxic tenocytes were THSB1, NSEP1, ITIH4 and TN-C. These findings were confirmed at the mRNA and protein level in the hypoxic ADMSCs and tenocytes. These proteins are involved in multiple signaling pathways of ECM repair/regeneration. This warrants further investigations for their translational significance in the management of RCTI.

Association of SIRT1 gene polymorphism and its expression for the risk of alcoholic fatty liver disease in the Han population

OBJECTIVE

To investigate the associations between SIRT1 polymorphisms and their expression in patients with alcoholic fatty liver disease (AFLD).

METHODS

A total of 268 heavy drinkers were divided into the AFLD group (n = 176) and alcoholic control (n = 92) and 237 light-/non-drinkers into the NAFLD (non-AFLD) group (n = 117) and healthy control (n = 120). The genotyping of SIRT1 (rs33957861, rs11599176, rs12413112 and rs35689145) was detected by the Sequenom MassARRAY iPLEX test. The mRNA and protein expressions of SIRT1 were determined by quantitative real-time polymerase chain reaction (qRT-PCR) and enzyme-linked immunosorbent assays (ELISA), respectively.

RESULTS

SIRT1 gene rs33957861 and rs11599176 polymorphisms significantly reduce the risk of NAFLD and AFLD, while rs35689145 remarkably increases the risk. Haplotypes of AAAA (rs33957861-rs11599176-rs12413112-rs35689145), AAAA, CAGA and CGAA can appreciably lower the presence of AFLD, but CAAG had an elevated AFLD risk. Besides, in the NAFLD and AFLD groups, a decreased BMI was found in the mutant genotype carriers of rs33957861, rs11599176 and rs12413112, but an increased BMI was observed in the rs35689145 mutant genotype carriers when compared to those with the wild-type homozygous genotype ones. Furthermore, rs33957861 C>T, rs11599176 A>G and BMI were independent risk factors of AFLD. There was no difference among four SNPs of SIRT1 and its mRNA and protein expressions in all groups.

CONCLUSION

SIRT1 polymorphisms and their expression were associated with the presence of AFLD, and there was a close relationship among four SNPs and BMI in AFLD patients, but no SNP was related to its expression.