YAP1 promotes high glucose-induced inflammation and extracellular matrix deposition in glomerular mesangial cells by modulating NF-κB/JMJD3 pathway

H2S donor SPRC ameliorates cardiac aging by suppression of JMJD3, a histone demethylase

Aims：S-propargyl-cysteine (SPRC) is an endogenous hydrogen sulfide (H2S) donor obtained by modifying the structure of S-allyl cysteine in garlic. This study aims to investigate the effect of SPRC on mitigating cardiac aging and the involvement of JMJD3, a histone demethylase, which represents the primary risk factor in major aging related diseases, in this process, elucidating the preliminary mechanism through which SPRC regulation of JMJD3. Results：In vitro, SPRC mitigated the elevated levels of reactive oxygen species (ROS), senescence-associated β-galactosidase (SA-β-gal), p53, and p21, reversing the decline in mitochondrial membrane potential (ΔΨm), which represented a reduction in cellular senescence. In vivo, SPRC improved Dox-induced cardiac pathological structure and function. Overexpression of JMJD3 accelerated cardiomyocytes and cardiac senescence, whereas its knockdown in vitro reduced the senescence phenotype. The potential binding site of the upstream transcription factor of JMJD3, XBP1s, was determined using online software. SPRC promoted the expression of cystathionine γ-lyase (CSE), which subsequently inhibited the IRE1α/XBP1s signaling pathway and decreased JMJD3 expression. Innovations：This study is the first to establish JMJD3 as a crucial regulator of cardiac aging. SPRC can alleviate cardiac aging by up-regulating CSE and inhibiting endoplasmic reticulum stress pathways, which in turn suppressing JMJD3 expression. Conclusions: JMJD3 plays an essential role in cardiac aging regulation, while SPRC can suppress the expression of JMJD3 by up-regulating CSE, thus delaying cardiac aging, which suggests that SPRC may serve as an aging protective agent and pharmacological targeting of JMJD3 may also be a promising therapeutic approach in age-related heart diseases.

Diphenyl Diselenide Alleviates Tert-Butyl Hydrogen Peroxide-Induced Oxidative Stress and Lipopolysaccharide-Induced Inflammation in Rat Glomerular Mesangial Cells

Hyperglycemia, oxidative stress, and inflammation play key roles in the onset and development of diabetic complications such as diabetic nephropathy (DN). Diphenyl diselenide (DPDS) is a stable and simple organic selenium compound with anti-hyperglycemic, anti-inflammatory, and anti-oxidative activities. Nevertheless, in vitro, the role and molecular mechanism of DPDS on DN remains unknown. Therefore, we investigated the effects of DPDS on tert-butyl hydrogen peroxide (t-BHP)-induced oxidative stress and lipopolysaccharide (LPS)-induced inflammation in rat glomerular mesangial (HBZY-1) cells and explored the underlying mechanisms. DPDS attenuated t-BHP-induced cytotoxicity, concurrent with decreased intracellular ROS and MDA contents and increased SOD activity and GSH content. Moreover, DPDS augmented the protein and mRNA expression of Nrf2, HO-1, NQO1, and GCLC in t-BHP-stimulated HBZY-1 cells. In addition, DPDS suppressed LPS-induced elevations of intracellular content and mRNA expression of interleukin (IL)-6, IL-1β and TNF-α. Furthermore, LPS-induced NFκB activation and high phosphorylation of JNK and ERK1/2 were markedly suppressed by DPDS in HBZY-1 cells. In summary, these data demonstrated that DPDS improves t-BHP-induced oxidative stress by activating the Nrf2/Keap1 pathway, and also improves LPS-induced inflammation via inhibition of the NFκB/MAPK pathways in HBZY-1 cells, suggesting that DPDS has the potential to be developed as a candidate for the prevention and treatment of DN.

JMJD family proteins in cancer and inflammation

The occurrence of cancer entails a series of genetic mutations that favor uncontrollable tumor growth. It is believed that various factors collectively contribute to cancer, and there is no one single explanation for tumorigenesis. Epigenetic changes such as the dysregulation of enzymes modifying DNA or histones are actively involved in oncogenesis and inflammatory response. The methylation of lysine residues on histone proteins represents a class of post-translational modifications. The human Jumonji C domain-containing (JMJD) protein family consists of more than 30 members. The JMJD proteins have long been identified with histone lysine demethylases (KDM) and histone arginine demethylases activities and thus could function as epigenetic modulators in physiological processes and diseases. Importantly, growing evidence has demonstrated the aberrant expression of JMJD proteins in cancer and inflammatory diseases, which might serve as an underlying mechanism for the initiation and progression of such diseases. Here, we discuss the role of key JMJD proteins in cancer and inflammation, including the intensively studied histone lysine demethylases, as well as the understudied group of JMJD members. In particular, we focused on epigenetic changes induced by each JMJD member and summarized recent research progress evaluating their therapeutic potential for the treatment of cancer and inflammatory diseases.

High glucose stimulating ECM remodeling and an inflammatory phenotype in the IPFP via upregulation of MFAP5 expression

Extracellular matrix (ECM) remodeling and inflammation in the infrapatellar fat pad (IPFP) are associated with cartilage degeneration and the severity of osteoarthritis (OA). Diabetes is associated with the progression of OA. However, it is still unclear whether diabetes can promote osteoarthritis by targeting the IPFP. In this study, we established a high-fat diet/streptozotocin (HFD/STZ)-induced diabetes mouse model. We found that fibrosis and inflammation were more severe in the IPFP in diabetic mice. Transcriptomic profiling showed that MFAP5 expression was upregulated in IPFPs collected from diabetic mice compared to IPFPs collected from normal mice. We identified that Pdgfrα(+) progenitors were the primary source of MFAP5 in the IPFP under diabetic conditions. In addition, high glucose promoted the expression of MFAP5 in Pdgfrα(+) progenitors by stimulating the translocation of Yap1. Overexpression of MFAP5 in Pdgfrα(+) progenitors promoted fibrogenic differentiation and the production of IL-6. Knocking down the expression of MFAP5 efficiently prevented fibrosis and decreased the level of IL-6 in the IPFP and attenuated cartilage degeneration. Together, these results suggest that MFAP5 may be a potential novel therapeutic target for the treatment of diabetes-induced OA.