Nuclear factor erythroid-2-related factor 2 (Nrf2) is a protein of the leucine zipper family, which mitigates inflammation and employs cytoprotective effects. Attempting to unravel the epigenetic regulation of type 2 diabetes mellitus (T2DM) and diabetic foot ulcer (DFU), we profiled the expression of eleven isoform-specific histone deacetylases (HDACs) and correlated them with NRF2 and cytokines. This study recruited a total of 60 subjects and categorized into DFU patients (n = 20), T2DM patients (n = 20), and healthy controls (n = 20). The DFU patients were subcategorized into uninfected and infected DFU (n = 10 each). We observed a progressive decline in the expression of NRF2 and its downstream targets among T2DM and DFU subjects. The inflammatory markers IL-6 and TNF-α were significantly upregulated, whereas anti-inflammatory marker IL-10 was significantly downregulated in DFU. Of note, a significant upregulation of HDAC1, 3, 4, 11, SIRT3 and downregulation of HDAC2,8, SIRT1, SIRT2, SIRT3, SIRT7 among DFU patients were observed. The significant positive correlation between NRF2 and SIRT1 in DFU patients suggested the vital role of NRF2/SIRT1 in redox homeostasis and angiogenesis. In contrast, the significant negative correlation between NRF2 and HDAC1, 3 and 4, implied an imbalance in NRF2-HDAC1, 3, 4 circuit. Furthermore, a significant positive correlation was observed between HDAC4 and IL-6, and the negative correlation between SIRT1 and IL-6 suggested the pro-inflammatory role of HDAC4 and the anti-inflammatory role of SIRT1 in NRF2 signaling. In conclusion, the epigenetic changes such as upregulation of HDAC1, 3, 4, 11, SIRT3 and downregulation of HDAC2, 8, SIRT1, SIRT2, SIRT6, SIRT7 and their association with NRF2 as well as inflammatory markers are suggestive of their roles in pathophysiology of T2DM and DFU.

The genetic polymorphism in the nuclear factor erythroid 2-related factor 2 (Nrf2) gene has been reported as one of the prognosis markers for various diseases, including cancer. Nrf2 is a key transcription factor involved in wound healing by regulating angiogenesis. We investigated the genetic association of NRF2 single-nucleotide polymorphism rs35652124 with T2DM and DFU and assessed its functional impact. A total of 400 subjects were recruited for the study and categorized into three groups: infected DFU patients (DFU, n=100), T2DM patients without complications (T2DM, n=150), and healthy adults with normal glucose tolerance (NGT, n=150). The subjects were genotyped by PCR-RFLP, and the polymorphism was identified by bidirectional Sanger sequencing. The expression of NRF2, IL-10, TNF-α, and IL-6 was studied by qPCR to evaluate the functional impact of rs35652124. The “TT” genotype of rs35652124 was associated with a significant risk for T2DM [OR=2.2 (1.2-4.2), p=0.01] and DFU [OR=7.9 (4-14.9), p<0.0001]. A significant decrease in transcriptional levels of NRF2 and IL-10 and a remarkable increase in TNF-α and IL-6 were observed in subjects with TT genotype. In conclusion, rs35652124 (TT) is a harmful genetic variant that predisposes to insulin resistance and impaired angiogenesis. Hence, it may serve as a diagnostic genetic marker for T2DM and DFU in combination with different inflammatory markers.

Objective: The present study was undertaken to examine the effect of phagocytosis of killed yeast on the induction of apoptosis in monolayer of HeLa cells. Methods: HeLa cell line was incubated with different doses (1000-7.8 μg/ml) of heat-killed Saccharomyces cerevisiae for 24, 48, and 72 hrs. The cytotoxicity against HeLa cell line during different exposure hours was screened by 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-tetrazolium bromide assay. Induction of apoptosis was further confirmed by morphological and biochemical examination. Antiproliferative effect of yeast was examined under inverted microscope. Cell morphological changes were analyzed by fluorescent staining with propidium iodide. Results: The results showed that yeast induces cytotoxicity against HeLa cells in concentrations and during prolonged exposure periods. The viability of HeLa cells decreased from 85% to 45% during 72 hrs of treatment with 1000 μg/ml of yeast cells. The inhibitory concentration 50% of heat-killed yeast required to induce 50% inhibition of HeLa cells was 62.5 μg/ml. Apoptotic cells showed signs such as cell enlargement, membrane blebbing, and chromatin condensation. Furthermore, cell cycle analysis showed that S. cerevisiae treated HeLa cells and showed a typical apoptosis pattern of DNA content that reflected sub-G0 phase (corresponding to apoptotic cells). Conclusion: Results from the present work show that the heat-killed yeast has anticancer activity and it includes apoptosis of HeLa cells in vitro.