Theacrine enhances autophagy and inhibits inflammation via regulating SIRT3/FOXO3a/Parkin pathway.

BACKGROUND: Psoriasis, a common chronic inflammatory skin condition, impacts around 2%-3% of the global population. Theacrine is recognized for its potential anti-inflammatory and antioxidant properties. However, the role of theacrine in psoriasis remains unclear. PURPOSES: To investigate the effects of theacrine on psoriasis and explore the underlying signaling pathways. METHODS: For imiquimod (IMQ)-induced Psoriasis-like mice, the psoriatic inflammation was monitored using Psoriasis Area and Severity Index (PASI). The skin damage was observed using Hematoxylin and Eosin staining. The KI67 and CD4 in skin tissues were assessed using Immunohistochemistry analysis. Western blots were performed to evaluate the expression of Keratin 1 (KRT1), KRT6, LC3, P62, Beclin1, T-bet, GATA3, RAR-related orphan receptor (ROR)-γt, Sirtuin-3 (SIRT3), Forkhead Box O3a (FOXO3a) and Parkin. Additionally, LC3B expression was analyzed using an immunofluorescent assay, while flow cytometry was performed to analyze the percentage of Th17, Th1, and Th2 positive cells in skin-draining lymph node. RESULTS: Theacrine improved skin condition by reducing hyperkeratosis and acanthosis, lowering PASI scores, and decreasing KI67-positive cells. Theacrine also modulated keratin expression, elevating KRT1 while reducing KRT6 levels. Theacrine enhanced autophagy indicated by an increased LC3-II/LC3-I ratio and Beclin1, while reduced P62 levels. Additionally, Theacrine reduced CD4-positive cells and suppressed Th17 and Th1 cell activation. Theacrine activated the FOXO3a/Parkin pathway by upregulating SIRT3 expression, and down-regulation of SIRT3 counteracted theacrine's effects in psoriasis-like mice. CONCLUSION: Theacrine inhibits skin damage, promotes autophagy, and mediates inflammation in IMQ-induced psoriasis mice via upregulating SIRT3 to activate FOXO3a/Parkin pathway, positioning theacrine as a candidate for psoriasis treatment.

Vitamin D3 alleviates lung fibrosis of type 2 diabetic rats via SIRT3 mediated suppression of pyroptosis.

PURPOSE: We aimed to evaluate whether pulmonary fibrosis occurs in type 2 diabetes rat models and whether VD3 can prevent it by inhibiting pyroptosis. METHODS: Sprague-Dawley rats were assigned to normal control (NC), diabetic model control (MC), low-dose VD3 (LVD), medium-dose VD3 (MVD), high-dose VD3 (HVD) and metformin positive control (PC) groups. Type 2 diabetes model was induced by a high-sugar, high-fat diet combined with STZ injection, and subsequently intervened with VD3 or metformin for 10 weeks. Blood glucose, body weight, food intake, water intake, urine volume, morphology, lung hydroxyproline level, immunohistochemistry, TUNEL staining, inflammatory cytokines secretion and related protein expression were analyzed. RESULTS: Diabetic rats exhibited significant impairments in fasting blood glucose, insulin resistance, body weight, food intake, water intake, and urine volume. While morphological parameters, diabetic rats exhibited severe lung fibrosis. Intriguingly, VD3 intervention reversed, at least in part, the diabetes-induced alterations. The expression of pyroptosis-related proteins was up-regulated in diabetic lungs whereas the changes were reversed by VD3. In the meanwhile, SIRT3 expression was down-regulated in diabetic lungs while VD3 up-regulated it. CONCLUSION: Fibrotic changes were observed in diabetic rat lung tissue and our study indicates that VD3 may effectively ameliorate diabetic pulmonary fibrosis via SIRT3-mediated suppression of pyroptosis.

Citicoline ameliorates arsenic-induced hepatotoxicity and diabetes in mice by overexpression of VAMP2, PPAR-γ, As3MT, and SIRT3.

The use of arsenic in arsenic-based pesticides has been common in many countries in the past and today. There is considerable evidence linking arsenic exposure to hepatotoxicity and diabetes. Destructive phenomena such as hepatic oxidative stress and inflammation can interfere with glucose uptake and insulin function. In the present study, the antioxidant, anti-inflammatory, and molecular mechanism of citicoline against sodium arsenite-induced hepatotoxicity and glucose intolerance were investigated in mice. Citicoline improved glucose tolerance impaired by sodium arsenite. Citicoline increased the hepatic activity of catalase, superoxide dismutase, and glutathione peroxidase enzymes. Moreover, we found that citicoline prevents an increase in the levels of thiobarbituric acid reactive substances. Citicoline reduced levels of caspase 3, tumor necrosis factor-alpha, and interleukin 6 in sodium arsenite intoxicated groups. It was shown that citicoline increased the expression of arsenite methyltransferase, vesicle-associated membrane protein 2, peroxisome proliferator-activated receptor gamma, and sirtuin 3 to combat sodium arsenite toxicity. Citicoline reduced glucose intolerance, which was disrupted by sodium arsenite, by affecting the pancreatic and extra-pancreatic pathways involved in insulin production, secretion, and action. Based on our results, citicoline can be considered a modulating agent against arsenic-induced hepatotoxicity and hyperglycemia. Considering the relationship between arsenic exposure and the occurrence of side effects such as liver toxicity and diabetes, it is necessary to monitor and awareness of arsenic residues from sources such as drinking water.

Clinical significance of SIRT3 and inflammatory factors in multiple myeloma patients with bortezomib-induced peripheral neuropathy: a cohort study.

The present study aimed to investigate the role of SIRT3 and inflammatory factors in bortezomib-induced peripheral neuropathy (PN). This prospective observational cohort study included a total of 159 patients of multiple myeloma patients during June 2016 to June 2019. All patients received the strategy of bortezomib and dexamethasone and were further divided into the PN group and the non-PN group. Serum SIRT3, CRP, IL-6 and TNF-α levels were measured by enzyme-linked immunosorbent assay (ELISA). During the study period, 76 (47.8%) patients developed PN. The inflammatory factors all gradually decreased and SIRT3 levels were gradually increased after treatment by bortezomib combined with dexamethasone compared with the baseline. The levels of all inflammatory factors were markedly higher, while SIRT3 levels were lower in PN patients compared with the non-PN patients at the same time point after treatment. In PN grade III patients, the serum levels of CRP, IL-6 and TNF-α were significantly higher, while serum levels of SIRT3 were markedly lower than the grade I-II patients. SIRT3 was negatively correlated with CRP, IL-6 and TNF-α. After nursing treatment and reduction of bortezomib dose, the levels of SIRT3 significantly increased, while levels of inflammatory decreased in PN patients with grade III. SIRT3 and inflammatory factors showed the potential for diagnosis of bortezomib-induced PN. Besides, SIRT3, IL-6 and TNF-α were the independent risk factors for MM patients developing PN after treatment of bortezomib. Higher inflammatory factors and lower SIRT3 might be associated with the development of bortezomib-induced PN in multiple myeloma patients, which might be reversed by decreased bortezomib dose and proper nursing treatment.

Emerging role of SIRT3 in mitochondrial dysfunction and cardiovascular diseases.

As a nicotinamide adenine dinucleotide (NAD)+-dependent protein deacetylase, SIRT3 is highly expressed in tissues with high metabolic turnover and mitochondrial content. It has been demonstrated that SIRT3 plays a critical role in maintaining normal mitochondrial biological function through reversible protein lysine deacetylation. SIRT3 has a variety of substrates that are involved in mitochondrial biological processes such as energy metabolism, reactive oxygen species production and clearance, electron transport chain flux, mitochondrial membrane potential maintenance, and mitochondrial dynamics. In the suppression of SIRT3, functional deficiencies of mitochondria contribute to the development of various cardiovascular disorders. Activation of SIRT3 may represent a promising therapeutic strategy for the improvement of mitochondrial function and the treatment of relevant cardiovascular disorders. In the current review, we discuss the emerging roles of SIRT3 in mitochondrial derangements and subsequent cardiovascular malfunctions, including cardiac hypertrophy and heart failure, ischemia-reperfusion injury, and endothelial dysfunction in hypertension and atherosclerosis.