Fluorofenidone protects against renal fibrosis by inhibiting STAT3 tyrosine phosphorylation.

Signaling through the Janus kinase/signal transducers and activators of transcription (JAK/STAT) pathway, especially JAK2/STAT3, is involved in renal fibrosis. Fluorofenidone (FD), a novel pyridone agent, exerts anti-fibrotic effects in vitro and in vivo. Herein, we sought to investigate whether FD demonstrates its inhibitory function through preventing JAK2/STAT3 pathway. In this study, we examined the effect of FD on activation of rat renal interstitial fibroblasts, glomerular mesangial cells (GMC), and expression of JAK2/STAT3. Moreover, we explored the histological protection effects of FD in UUO rats, db/db mice, and phosphorylation of JAK2/STAT3 cascade. Our studies found that pretreatment with FD resulted in blockade of activation of fibroblast and GMC manifested by fibronectin (FN) and α-smooth muscle actin (α-SMA) protein expression and decline of STAT3 tyrosine phosphorylation induced by IL-6 or high glucose. In unilateral ureteral obstruction rats and a murine model of spontaneous type 2 diabetes (db/db mice), treatment with FD blocked the expression of FN and α-SMA, prevented renal fibrosis progression, and attenuated STAT3 activation. However, FD administration did not interfere with JAK2 activation both in vivo and in vitro. In summary, the molecular mechanism by which FD exhibits renoprotective effects appears to involve the inhibition of STAT3 phosphorylation.

Losartan inhibits LPS + ATP-induced IL-1beta secretion from mouse primary macrophages by suppressing NALP3 inflammasome.

OBJECTIVES: IL-1beta is a potent proinflammatory, pro-fibrogenetic and pro-athrosclerosis cytokine which has been shown to play an important role in an expanding number of noninfectious, chronic inflammatory conditions including cardiovascular disease, renal fibrosis, rheumatoid arthritis and even type 2 diabetes. Losartan is an angiotensin II receptor antagonist widely used for the treatment of hypertension, diabetic nephropathy and congestive heart failure. In this study, we attempted to clarify whether losartan has an inhibitory effect on IL-1beta. To further elucidate the molecular mechanism underlying the anti-IL-1beta property of losartan, we studied the LPS+ATP-induced activation of NALP3 inflammasome which controls the muturation and secretion of IL-1beta. METHODS: LPS and ATP were used to stimulate the release of IL-1beta from thioglycollate-elicited macrophages from BALB/c mice. The production of IL-1beta was evaluated by ELISA assay and NALP3, caspase-1, IL-beta mRNA levels were determined by reverse transcription-polymerase chain reaction. RESULTS: In cultured thioglycollate-elicited macrophages, we observed that LPS + ATP greatly enhanced IL-1 beta secretion (6938.00 +/- 83.45; P < 0.05) and the mRNA levels of NALP3, caspase-1 which are two main components of NALP3 inflammasome (60.88 +/- 8.28; 1.31 +/- 0.04, P < 0.05 for both). The macrophages co-cultured with losartan showed low production of IL-1beta (3907.50 +/- 143.61; P < 0.05) and low production of NALP3, caspase-1mRNA (29.82 +/- 6.92; 1.12 +/- 0.05, P < 0.05 for both). Losartan did not reduce IL-1beta mRNA(P > 0.05). CONCLUSIONS: Our results show that the NALP3 inflammasome is up-regulated and activated in the mouse macrophage in response to LPS + ATP stimulation. Losartan is able to suppress the LPS + ATP-induced production of IL-1beta protein. In addition, this effectmay be partially mediated by suppressing NALP3 inflammasome activation.

[Source and Cause Analysis of High Concentration of Inorganic Aerosol During Two Typical Pollution Processes in Winter over Tianjin].

Inorganic aerosol is the main component of haze days in winter over Tianjin. In this study, two typical high concentrations of secondary inorganic aerosol (SIA) processes, defined as CASE1 and CASE2, were selected during polluted days in January 2020 over Tianjin, and the effects of meteorological factors, regional transport, and chemical processes were comprehensively investigated combined with observations and numerical models (WRF-NAQPMS). The average SIA concentrations in CASE1 and CASE2 were 76.8 µg·m-3 and 66.0 µg·m-3, respectively, and the nitrate concentration was higher than that of sulfate and ammonium, which were typical nitrate-dominated pollution processes. Meteorological conditions played a role in inorganic aerosol formation. The temperature of approximately -6-0℃ and 2-4℃ and the relative humidity of 50%-60% and 80%-100% would be suitable conditions for the high SIA concentration (>80 µg·m-3) in CASE1, whereas the temperature of approximately 2-4℃ and the relative humidity of 60%-70% would be suitable in CASE2. The average contribution rates of external sources to SIA in the CASE1 and CASE2 processes were 62.3% and 22.1%, which were regional transport-dominant processes and local emission-dominant processes, respectively. The contribution of the local emission of CASE1 to nitrate and sulfate was 16.2 µg·m-3 and 8.2 µg·m-3, respectively, higher than that of external sources (31.7 µg·m-3 and 8.8 µg·m-3). the local contribution of CASE2 to nitrate and sulfate was 29.3 µg·m-3 and 25.1 µg·m-3, respectively, whereas the contribution from external sources was 8.1 µg·m-3 and 9.4 µg·m-3, respectively. The quantitative result indicated that local formation and regional transport resulted in higher nitrate concentration than sulfate in CASE1, in contrast to only local sources in CASE2. The gas phase reaction was the main source of inorganic aerosol formation, contributing 48.9% and 57.8% in CASE1 and CASE2, respectively, whereas the heterogeneous reactions were also important processes, with contribution rates of 48.1% and 42.2% to SIA. The effect of aqueous phase reaction was negligible.

Crohn's disease as the intestinal manifestation of pan-lymphatic dysfunction: An exploratory proposal based on basic and clinical data.

Crohn's disease (CD) is caused by immune, environmental, and genetic factors. It can involve the entire gastrointestinal tract, and although its prevalence is rapidly increasing its etiology remains unclear. Emerging biological and small-molecule drugs have advanced the treatment of CD; however, a considerable proportion of patients are non-responsive to all known drugs. To achieve a breakthrough in this field, innovations that could guide the further development of effective therapies are of utmost urgency. In this review, we first propose the innovative concept of pan-lymphatic dysfunction for the general distribution of lymphatic dysfunction in various diseases, and suggest that CD is the intestinal manifestation of pan-lymphatic dysfunction based on basic and clinical preliminary data. The supporting evidence is fully summarized, including the existence of lymphatic system dysfunction, recognition of the inside-out model, disorders of immune cells, changes in cell plasticity, partial overlap of the underlying mechanisms, and common gut-derived fatty and bile acid metabolism. Another benefit of this novel concept is that it proposes adopting the zebrafish model for studying intestinal diseases, especially CD, as this model is good at presenting and mimicking lymphatic dysfunction. More importantly, the ensuing focus on improving lymphatic function may lead to novel and promising therapeutic strategies for CD.

Antagonizing adipose tissue-derived exosome miR-103-hepatocyte phosphatase and tensin homolog pathway alleviates autophagy in non-alcoholic steatohepatitis: A trans-cellular crosstalk.

BACKGROUND: Obesity plays a vital role in the occurrence and development of non-alcoholic steatohepatitis (NASH). However, the underlining mechanism is still unclear, where adipose tissue (AT) derived exosomes may actively participate. MicroRNAs (miRNAs) are commonly secreted from exosomes for cell communication. Though the regulation of miR-103 on insulin sensitivity has been reported, the specific role of AT-derived exosomes miR-103 in NASH is still vague and further investigation may provide novel therapeutic choices. AIM: To determine the specific role of AT-derived exosomes miR-103 in developing NASH through various methods. METHODS: The expression levels of miR-103 in the AT-derived exosomes and livers were detected and compared between NASH mice and control. The effect of miR-103 on NASH progression was also explored by antagonizing miR-103, including steatosis and inflammation degree changes. The interaction between miR-103 and the autophagy-related gene phosphatase and tensin homolog (PTEN) was confirmed by dual-luciferase reporter assay. The role of the interaction between miR-103 and PTEN on autophagy was verified in NASH-like cells. Finally, the effects of miR-103 from adipose-derived exosomes on NASH and autophagy were analyzed through animal experiments. RESULTS: The expression of miR-103 was increased in NASH mice, compared to the control, and inhibition of miR-103 could alleviate NASH. The results of the dual-luciferase reporter assay showed miR-103 could interact with PTEN. MiR-103-anta decreased p-AMPKa, p-mammalian target of rapamycin (mTOR), and p62 but increased the protein levels of PTEN and LC3-II/I and the number of autophagosomes in NASH mice. Similar results were also observed in NASH-like cells, and further experiments showed PTEN silencing inhibited the effect of miR-103-anta. AT derived-exosome miR-103 aggravated NASH and increased the expressions of p-AMPKa, p-mTOR, and p62 but decreased the protein levels of PTEN and LC3-II/I and the number of autophagosomes in mice. CONCLUSION: AT derived-exosome increased the levels of miR-103 in the liver, and miR-103 aggravated NASH. Mechanically, miR-103 could interact with PTEN and inhibit autophagy.

Synthesis and structure-activity relationship of 5-substituent-2(1H)-pyridone derivatives as anti-fibrosis agents.

Pyridone compounds, such as pirfenidone (PFD) and fluorofenidone (AKF-PD), are multi-target anti-fibrotic agents. Using PFD and AKF-PD as the leading compounds, two series of novel (5-substituent)-2(1H)-pyridone compounds were synthesized with the purpose of maintaining multi-targeting property and overcoming the drawbacks of fast metabolism. These derivatives demonstrated good proliferation inhibiting activity against NIH3T3 cells by MTT assay with AKF-PD as the positive control. Compound 5b exhibited a high potent of anti-fibrosis with a IC(50) of 0.08 mmol/L about 34 times of AKF-PD. The SAR of pyridone derivatives as anti-fibrosis agents was also discussed.

High-fat diet aggravates colitis via mesenteric adipose tissue derived exosome metastasis-associated lung adenocarcinoma transcript 1.

BACKGROUND: Obesity is associated with an increased risk of developing Crohn's disease (CD), higher disease activity, and comparatively worse clinical outcomes. AIM: To investigate the role of mesenteric adipose tissue-derived exosomes in the pathogenesis of CD aggravation in obese individuals. METHODS: First, we induced colitis in mice initiated on high-fat and normal diets and compared the severity of colitis. We then extracted and identified exosomes from mesenteric adipose tissue and determined the levels of metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) in mesenteric adipose tissue-derived exosomes and the colon. Next, we demonstrated an interaction between MALAT1 and the miR-15a-5p/activating transcription factor 6 (ATF6) axis. Finally, we explored the effects of mesenteric adipose tissue-derived exosomes extracted from mice fed a high-fat or normal diet on the severity of 2,4,6-trinitrobe-nzenesulfonic acid (TNBS)-induced colitis and ATF6-related endoplasmic reticulum stress pathways. RESULTS: High-fat diet was found to aggravate TNBS-induced colitis in mice. The expression of MALAT1 in mesenteric adipose tissue-derived exosomes of high-fat diet-fed mice increased. The increased expression of MALAT1 in colon tissue exacerbated TNBS-induced colitis and activated the ATF6 endoplasmic reticulum stress pathway. This effect was partially reversed by the reduced expression of MALAT1 and overexpression of miR-15a-5p. CONCLUSION: Mesenteric adipose tissue-derived exosome-encapsulated long noncoding RNAs MALAT1 targets the colon and aggravates TNBS-induced colitis in obese mice, which may potentially act on the miR-15a-5p/ATF6 axis and activate endoplasmic reticulum stress.

Fluorofenidone attenuates diabetic nephropathy and kidney fibrosis in db/db mice.

BACKGROUND/AIMS: Fluorofenidone [1-(3-fluorophenyl)-5-methyl-2-(1H)-pyridone, AKF-PD], a novel pyridone agent, showed potent antifibrotic properties. The aim of the present study was to investigate the effects of AKF-PD on diabetic nephropathy and kidney fibrosis, and to obtain an insight into its mechanisms of action. METHODS: We administered AKF-PD to diabetic db/db mice for 12 weeks. Moreover, we performed in vitro cultures using murine mesangial cells exposed to high ambient glucose concentrations. RESULTS: AKF-PD reduced renal hypertrophy, mesangial matrix expansion and albuminuria in the db/db mice. The upregulated expression of α1(I)- and α1(IV)-collagen and fibronectin mRNAs, transforming growth factor-ß1 (TGF-ß1), α-smooth muscle actin (α-SMA), and tissue inhibitors of metalloproteinase 1 (TIMP-1) mRNAs and proteins was inhibited by AKF-PD treatment in the renal cortex of db/db mice. The maximal effective dose of AKF-PD was about 500 mg/kg body weight. AKF-PD inhibited the upregulated expression of α1(I)- and α1(IV)-collagens, TGF-ß1, TIMP-1 and α-SMA induced by high glucose concentrations in cultured mesangial cells. CONCLUSIONS: Our data indicate that AKF-PD diminishes the abnormal accumulation of mesangial matrix through the inhibition of upregulated expression of TGF-ß target genes in kidneys of db/db mice, resulting in attenuation of renal fibrosis and amelioration of renal dysfunction despite persistent hyperglycemia. Therefore, AKF-PD, a potent antifibrotic agent, holds great promise in the treatment of diabetic nephropathy.

[Impact of rosuvastatin on atherosclerosis lesions in apolipoprotein E knockout mice].

OBJECTIVE: To investigate the effect of rosuvastatin on atherosclerosis in apoE-knockout (apoE-/-) mice. METHODS: Eighteen 6-week-old apoE-/- mice fed with high fat diet were used as atherosclerosis models, twelve 6-week-old C57BL/6 mice fed with normal diet were used as control. After twelve weeks, six apoE-/- mice were used to observe the formation of atherosclerosis. Another 12 apoE-/- mice were divided into placebo treated group (n = 6) and rosuvastatin group (n = 6, 10 mg×kg(-1)×d(-1) per gavage) and treated for 12 weeks. Then, blood was collected for measuring lipid, aorta was prepared for morphologic study (HE, Oil red O, Masson) and immunohistochemical analysis (α-smooth active protein, transforming growth factor ß(1), macrophage surface molecule-3). RESULTS: Serum cholesterol and low density lipoprotein levels were significantly higher in apoE-/- mice fed with high fat diet than in C57/BL6 mice(all P < 0.01)while triglyceride level was similar between the two groups, these were not affected by rosuvastatin. Similarly, atherosclerotic lesion area in apoE-/- mice fed with high fat diet was also not significantly reduced by rosuvastatin, while lipid deposition could be significantly reduced and collagen deposition could be significantly increased in the aortic atherosclerotic lesions by treatment with rosuvastatin. Upregulated TGF-ß(1) and Mac-3 expression in the aortic atherosclerotic lesions in apoE-/- mice fed with high fat diet could also be significantly reduced by rosuvastatin (all P < 0.01), suggesting reduce inflammatory responses in the atherosclerotic lesion and stable atherosclerotic plaque post rosuvastatin treatment. CONCLUSION: Reducing inflammatory responses and stabilizing plaque properties might contribute to the anti-atherosclerosis effects of rosuvastatin in mice high fat diet fed apoE-/- mice.

Response of microalgae Chlorella vulgaris to Cr stress and continuous Cr removal in a membrane photobioreactor.

This study evaluated the toxicity of Cr(VI) to microalgae Chlorella vulgaris, and its removal by continuous microalgae cultivation in membrane photobioreactor (MPBR). Batch cultivation in photobioreactors showed that low concentration of Cr(VI) (0.5 and 1.0 mg L-1) stimulated the growth of C. vulgaris, while 2.0 and 5.0 mg L-1 Cr(VI) in the wastewater significantly inhibited the growth of C. vulgaris. Superoxide dismutase and catalase activities that represented cellular antioxidant capacity significantly increased at 0.5 and 1.0 mg L-1 Cr(VI), and then gradually decreased with the continuous increase of Cr(VI) concentration. The content of malondialdehyde, which represents the degree of cellular oxidative damage, increased with the increase of Cr(VI) concentration and reached the peak value at 2.0 mg L-1 Cr(VI). C. vulgaris was then cultured in MPBR equipped with hollow-fiber ultrafiltration membrane module to achieve continuous removal of Cr from wastewater. With the in-situ solid-liquid separation function of the membrane module, solid retention time (SRT) and hydraulic retention time (HRT) of the reactor could be controlled separately. Experimental results showed that both SRT and HRT had significant effects on the algal biomass production and pollutants removal. During the continuous operation, MPBR achieved a maximum total Cr reduction of 50.0% at HRT of 3-day and SRT of 40-day, and a maximum volumetric removal rate of total Cr of 0.21 mg L-1 d-1 at HRT of 2-day and SRT of 40-day.

Palmitoylation in Crohn's disease: Current status and future directions.

S-palmitoylation is one of the most common post-translational modifications in nature; however, its importance has been overlooked for decades. Crohn's disease (CD), a subtype of inflammatory bowel disease (IBD), is an autoimmune disease characterized by chronic inflammation involving the entire gastrointestinal tract. Bowel damage and subsequent disabilities caused by CD are a growing global health issue. Well-acknowledged risk factors for CD include genetic susceptibility, environmental factors, such as a westernized lifestyle, and altered gut microbiota. However, the pathophysiological mechanisms of this disorder are not yet comprehensively understood. With the rapidly increasing global prevalence of CD and the evident role of S-palmitoylation in CD, as recently reported, there is a need to investigate the relationship between CD and S-palmitoylation. In this review, we summarize the concept, detection, and function of S-palmitoylation as well as its potential effects on CD, and provide novel insights into the pathogenesis and treatment of CD.

Simultaneous removal of nutrient and sulfonamides from marine aquaculture wastewater by concentrated and attached cultivation of Chlorella vulgaris in an algal biofilm membrane photobioreactor (BF-MPBR).

Microalgae based wastewater treatment has attracted increasing attention for its many advantages in recent years. In this study, a novel microalgae biofilm membrane photobioreactor (BF-MPBR) was developed for the efficient microalgae cultivation and the removal of nutrient and sulfonamides (SAs) from marine aquaculture wastewater. Two BF-MPBRs with hydraulic retention time (HRT) of 1 day and 2 days respectively were continuously operated for 70 days without harvesting microalgae. Concentrated and attached culture of marine Chlorella vulgaris was achieved in these continuous flow BF-MPBRs due to the suspended solid carriers and microfiltration membrane module in the reactors. The algal biomass productivity achieved in BF-MPBRs with HRT of 1 day and 2 days were 14.02 and 22.03 mg L-1 day-1, respectively. In addition, at the end of the cultivation, 60.4% and 45.0% of microalgae were fixed into algal biofilm in BF-MPBRs with 1 day and 2 day HRT, respectively. Compared with batch cultivation, more efficient nutrient and SAs removal performance was achieved in BF-MPBRs, although the HRT of the BF-MPBRs used in this study was only 1 or 2 days. During the stable operation stage of the BF-MPBRs, the reduction in dissolved inorganic nitrogen (DIN), dissolved inorganic phosphorus (DIP), sulfadiazine (SDZ), sulfamethazine (SMZ) and sulfamethoxazole (SMX) were found in the range of 91.0-99.6%, 92.1-98.4%, 61.0-79.2%, 50.0-76.7% and 60.8-82.1%, respectively. Therefore, nutrient and SAs were simultaneously and efficiently removed from marine aquaculture wastewater by microalgae cultivation in BF-MPBR.

Effect of organic carbon to nitrogen ratio in wastewater on growth, nutrient uptake and lipid accumulation of a mixotrophic microalgae Chlorella sp.

This study investigated the biomass/lipid production, nutrient removal and fatty acid composition of an isolated mixotrophic microalga (Chlorella sp. G-9) cultured in simulated wastewater with different TOC/TN ratio. As the TOC/TN ratio of wastewater increased from 0 to 24, the growth rate of Chlorella sp. G-9 increased gradually, but did not increase further at 30. Nutrient removal was related to microalgae growth. In the wastewater with TOC/TN ratio of 24 and 30, 99.58% and 99.61% nitrogen was removed, respectively. In conditions of initial TOC/TN ratios of 24 and 30, Chlorella sp. G-9 could accumulate lipid as high as 35.3% and 36.5%, respectively. The corresponding lipid productivities were 34.2 and 32.6 mg L-1 d-1, respectively, which were 13.7 and 13.0 times higher than those in photoautotrophic condition. Increasing the initial TOC/TN ratio of the wastewater could slightly increase the saturated degree in fatty acid, thereby improving the stability of biodiesel.