Tiron protects against nicotine-induced lung and liver injury through antioxidant and anti-inflammatory actions in rats in vivo

MS-275 facilitates osseointegration in osteoporotic rats by mitigating oxidative stress via activation of the miR-200a/Keap1/Nrf2 signaling pathway

OBJECTIVES

Osteoporosis, a prevalent metabolic bone disease affecting millions worldwide. Although MS-275 has been reported to inhibit oxidative stress, its ability to protect osteoblasts from oxidative stress damage has yet to be clarified. This study investigated whether MS-275 can inhibit oxidative stress and promote osteogenesis by activating the miRNA-200a/Keap1/Nrf2 signaling pathway.

METHODS

In vitro, MC3T3-E1 cells underwent induction with carbonyl cyanide 3-chlorophenylhydrazone, leading to the establishment of an oxidative stress model, investigating the underlying mechanism. In vivo, using a rat model of ovariectomized osteoporosis, evaluating the effects of MS-275.

RESULTS

In vitro, MS-275 treatment of oxidation-induced MC3T3-E1 cells resulted in up-regulation of osteoblast protein, increased expression of miRNA-200a, increased binding of miRNA-200a to Keap1 mRNA, decreased expression of Keap1 protein, and dissociation of Nrf2 from Keap1. The expressions of total Nrf2, nuclear Nrf2 and HO-1 were increased, mitochondrial function was enhanced, and oxidative damage was reduced. However, these effects were reversed after interference with miRNA-200a. In vivo,MS-275 effectively enhanced the microstructural features of distal femoral trabecular bone, increased the mineralization capacity of osteoblasts, and promoted bone formation.

DISCUSSION

MS-275 can reverse oxidative stress-induced cell damage, promote bone healing, and improve osteoporosis by activating the miRNA-200a/Keap1/Nrf2 pathway.

A comprehensive analysis of the impact of smoking on adverse clinical outcomes of steatotic liver diseases

Background

Metabolic dysfunction-associated steatotic liver disease (MASLD), previously known as non-alcoholic fatty liver disease (NAFLD), is an increasingly prevalent liver disorder.

Objectives

This study investigated the effect of smoking status on various clinical outcomes in MASLD and metabolic dysfunction and alcohol-associated liver disease (MetALD).

Design

This study is a retrospective cohort analysis utilizing data from the UK Biobank (Application ID: 117214). Participants were categorized as current, previous, or never smokers, and outcomes were analyzed using inverse probability of treatment weighting to adjust for confounders.

Methods

The primary outcomes were all-cause mortality and liver-related mortality. Secondary outcomes included incidence of liver cirrhosis, hepatic decompensation, cardio-cerebrovascular diseases (CVD), and hepatocellular carcinoma (HCC). Multivariate Cox proportional hazards models were employed to evaluate associations.

Results

Previous and never smokers had significantly lower hazard ratios (HRs) for mortality compared to current smokers in all cohorts (HR: 0.33, 95% confidence interval (CI): 0.31-0.35, p < 0.001 for never smokers in No SLD cohort, HR: 0.43, 95% CI: 0.41-0.44, p < 0.001 for never smokers in MASLD cohort, and HR: 0.41, 95% CI: 0.38-0.45, p < 0.001 for never smokers in MetALD cohort). Previous and never smokers showed significantly lower incidences of liver cirrhosis compared to current smokers across all cohorts, except for MetALD. Previous and never smokers showed lower incidences of CVD compared to current smokers. In the MASLD cohort, never smokers had the lowest incidence of hepatic decompensation and HCC. In the MetALD cohort, no significant differences were observed in the risk of hepatic decompensation and HCC between different smoking statuses.

Conclusion

Smoking is related to worse survival outcomes and higher incidences of liver cirrhosis and CVD in MASLD and MetALD cohorts. Therefore, smoking cessation and prevention are crucial strategies for reducing the burden of liver disease and improving patient prognosis.

Tiron enhances the anti-cancer activity of doxorubicin in DMBA-induced breast cancer: Role of Notch signaling/apoptosis/autophagy/oxidative stress

Existing work intended to investigate the outcomes of the localized mitochondrial antioxidant tiron (TR) alone or in combination with doxorubicin (DOX) in 7,12-dimethylbenz[a]anthracene (DMBA)-induced mammary carcinogenesis in rats and the mechanistic pathways behind these effects. Also, to examine the preventive role of TR against DOX-related cardiotoxicity. 64 female Sprague-Dawley rats were randomly assigned into 8 groups: CTRL, DOX, TR, DMBA, DMBA + DOX, DMBA + TR100, DMBA + TR200, and DMBA + DOX + TR200. Rats received TR (100 and 200 mg/kg), DOX (2mg/kg), and DMBA (7.5 mg/kg) for four consecutive weeks. TR alone or combined with DOX not only inhibited oxidative status-related parameters and Notch pathway proteins but also attenuated proliferation markers, and enhanced apoptosis, and autophagy-related genes. Consistently, the histopathological analysis showed better scores in mammary tissues isolated from groups treated with TR only or combined with DOX. Additionally, TR dramatically decreased relative heart weight, myocardial injury biomarkers, and heart oxidative stress parameters while maintaining the myocardial histological integrity. Here we provided evidence that TR acts via modulating Notch signaling/apoptosis/autophagy/oxidative stress to elicit anti-tumor activity and combination with DOX revealed a higher efficacy as a novel anticancer strategy. Moreover, TR could be a potential cardio-protective candidate during DOX-chemotherapy, possibly via its antioxidant activity.

Nicotine exacerbates liver damage in a mice model of Ehrlich ascites carcinoma through shifting SOD/NF-κB/caspase-3 pathways: ameliorating role of Chlorella vulgaris

Nicotine, a pervasive global environmental pollutant, is released throughout every phase of the tobacco's life cycle. This study examined the probable ameliorative role of Chlorella vulgaris (ChV) extract against nicotine (NIC)-induced hepatic injury in Ehrlich ascites carcinoma (EAC) bearing female Swiss mice. Sixty female Swiss mice were assigned to four equal groups orally gavaged 2% saccharin 0.2 mL/mouse (control group), orally intubated 100 mg ChV /kg (ChV group), orally intubated 100 µg/mL NIC in 2% saccharin (NIC group), and orally intubated NIC + ChV as in group 3 and 2 (NIC+ChV group). The dosing was daily for 4 weeks. Mice from all experimental groups were then inoculated intraperitoneally with viable tumor cells 2.5 × 106 (0.2 mL/mouse) in the fourth week, and the treatments were extended for another 2 weeks. The results have shown that NIC exposure significantly altered the serum levels of liver function indices, lipid profile, LDH, and ALP in the NIC-exposed group. NIC administration significantly increased hepatic inflammation, lipid peroxidation, and DNA damage-related biomarkers but reduced antioxidant enzyme activities. NIC exposure downregulated SOD1, SOD2, CAT, GPX1, and GPX2 but upregulated NF-κB hepatic gene expression. Notably, the presence of the EAC cells outside the liver was common in all mice groups. Liver tissue of the NIC-exposed group showed multifocal expansion of hepatic sinusoids by neoplastic cells. However, with no evidence of considerable infiltration of EAC cells inside the sinusoids or in periportal areas in the NIC + ChV groups. NIC significantly altered caspase-3, Bax, and BcL2 hepatic immune expression. Interestingly, ChV administration significantly mitigates NIC-induced alterations in hepatic function indices, lipid profile, and the mRNA expression of antioxidant and NF-κB genes and regulates the caspase-3, Bax, and BcL2 immunostaining. Finally, the in vivo protective outcomes of ChV against NIC-induced hepatic injury combined with EAC in female Swiss mice could suggest their helpful role for cancer patients who are directly or indirectly exposed to NIC daily.

Protective effect of Enicostemma axillare - Swertiamarin on oxidative stress against nicotine-induced liver damage in SD rats

OBJECTIVE

The current investigation was aimed to determine the hepatoprotective benefits of Swertiamarin (ST) administration against nicotine-induced hepatotoxicity in SD rats.

MATERIAL AND METHODS

A total of 48 adult male SD rats were allocated into six groups using a fully randomised approach. As a control, group I was given oral (PO) normal saline. For 65 days, the animals in groups II, III, IV, V and VI received 2.5mg/kg/day of nicotine intraperitoneally (IP), 100mg/kg/day of ST orally (PO), 200mg/kg/day of ST orally (PO), 2.5mg/kg/day of nicotine (IP)+100mg/kg/day of ST (PO), and 2.5mg/kg/day of nicotine (IP)+200mg/kg/day of ST (PO), respectively. Animals were killed on 66thday, liver tissue was removed and used for histopathological analysis as well as biochemical testing (oxidative stress parameters and liver function enzymes).

RESULTS

When compared to control animals, the animals in group II showed a substantial rise in their aspartate aminotransferase (AST), alanine aminotransferase (ALT), urea, and creatinine levels (P˂0.001). Furthermore, compared to control animals, these animals displayed enhanced hepatic oxidative stress as indicated by significantly higher Malondialdehyde (MDA) levels (P˂0.001) and lower levels of Catalase (CAT), Glutathione (GSH), Glutathione peroxidase (GSH-Px) and Superoxide dismutase (SOD) (P˂0.001). Further, more histological anomalies were seen in the liver of nicotine-treated rats compared to control rats, including significant vacuolization, poor tissue architecture, the growth of pycnotic nuclei, and dilated sinusoids. Contrary to nicotine-treated rats, the co-administration of ST and nicotine was observed to prevent the abnormalities caused by nicotine (groups V and VI).

CONCLUSION

The results of the current study show that nicotine can seriously harm liver tissue and that swertiamarin can prevent the harmful effects of nicotine on rat liver. Future research is necessary to delve deeply into the mechanisms behind swertiamarin protective impact against nicotine-induced hepatotoxicity.

Effects of nicotine on microRNA-124 expression in bile duct ligation-induced liver fibrosis in rats

BACKGROUND

Nicotine, the main compound of smoking may exert its effects by changing the expression of microRNAs (miRNAs). This study was conducted to further investigate the molecular mechanisms of miRNA-dependent effects of nicotine in an animal model of liver fibrosis.

METHODS

The bile duct ligation (BDL) approach was used to create a model of liver fibrosis. Twenty-four male Wistar rats were used in the study. The effects of nicotine administration on miRNA-124 expression, as well as alpha-smooth muscle actin (liver fibrosis marker) and chemokine ligand 2 (an inflammatory chemokine), were investigated using RT-qPCR. In addition, the mRNA and protein expression of signal transducer and activator of transcription 3 (STAT-3; as a potential target for miRNA-124) were investigated by RT-qPCR and immunofluorescence, respectively. Liver enzyme activity levels were measured using a colorimetric assay. In addition, the effects of nicotine on the process of liver fibrosis were investigated with histological studies.

RESULTS

The development of liver fibrosis in BDL rats and nicotine administration led to a decrease in miRNA-124 expression. The decrease in the expression is accompanied by the increase in the expression of fibrotic and proinflammatory genes. Also, an increase in STAT-3 mRNA and protein expression was observed in the fibrotic rats that received nicotine. In addition, the significant increase in bilirubin and liver enzymes in fibrotic rats worsens with nicotine administration. The results of histological studies also confirm these results.

CONCLUSION

Considering that miRNA-124 is an anti-inflammatory miRNA, it can be concluded that the decrease in its expression due to nicotine exposure leads to an increase in inflammatory processes and subsequently to an increase in liver fibrosis.

Dexpanthenol exhibits antiapoptotic and anti-inflammatory effects against nicotine-induced liver damage by modulating Bax/Bcl-xL, Caspase-3/9, and Akt/NF-κB pathways

Chronic tobacco use can lead to liver damage and inflammation due to the accumulation of various toxins in the body. This study aimed to investigate the correlation between the molecular mechanisms of nicotine-induced liver injury, the caspase cascade, and the Akt/NF-κB signaling pathway, as well as the protective effects of dexpanthenol (DEX). Male rats were subjected to intraperitoneal injections of nicotine at a concentration of 0.5 mg/kg/day and/or DEX at a concentration of 500 mg/kg/day for 8 weeks. After the treatment period, liver function tests were conducted on serum samples, and tissue samples were analyzed for protein levels of Akt, NF-κB, Bax, Bcl-xL, Caspase-3, and Caspase-9, along with histopathological changes. Additionally, assessments of oxidative stress markers and proinflammatory cytokines were carried out. Nicotine administration led to elevated levels of IL-6, IL-1β, MDA, TOS, and oxidative stress index, accompanied by decreased TAS levels. Moreover, nicotine exposure reduced the p-Akt/Akt ratio, increased NF-κB, Bax, Caspase-3, and Caspase-9 protein levels, and decreased the antiapoptotic protein Bcl-xL levels. DEX treatment significantly mitigated these effects, restoring the parameters to levels comparable to those of the control group. Nicotine-induced liver injury resulted in oxidative stress, inflammation, and apoptosis, mediated by Bax/Bcl-xL, Caspase-3, Caspase-9, and Akt/NF-κB pathways. Conversely, DEX effectively attenuated nicotine-induced liver injury by modulating apoptosis through NF-κB, Caspase-3, Caspase-9, Bax inhibition, and Bcl-xL activation.

Exploring cardiac impact of oral nicotine exposure in a transplantable Neoplasm Mice Model: Insights from biochemical analysis, morphometry, and molecular docking: Chlorella vulgaris green algae support

Nicotine-induced cardiac tissue damage is a concern for cancer patients, but the exact pathogenesis from nicotine oral exposure is unclear. This study was designed to investigate the impact of nicotine and Chlorella vulgaris (Ch. V) on cardiac glutathione homeostasis, inflammatory response, cardiac damage markers, apoptotic proteins and histopathological findings in an experimentally transplantable neoplasm mouse model (Ehrlich ascites carcinoma; EAC). In the in-vivo experiment, the female Swiss mice were divided into four groups: control, Ch.V (100 mg/kg), Nicotine (100 µg/ml/kg), and a combination group ( Nocotine+ Ch.V) for 40 days. Furthermore, in this study,the effects of C. vulgaris components on caspase-3, TNF-α, and IL-1β activity were explored using Molecular Operating Environment (MOE) docking software to ensure its ability to counteract the toxic effects of nicotine. The results indicated that nicotine has induced significant (P < 0.001) cardiopathic alterations in EAC-bearing mice with changes in cardiac tissue enzymes. C. Vulgaris attenuated the nicotine-induced cardiac glutathione inhibition, suppressed the inflammatory response, exerted antiapoptotic effects, mitigated myocardial injury biomarkers, and repaired cellular and tissue damage. Moreover, the molecular docking results revealed the ability of C. vulgaris to bind with interleukin-1 receptor type 1 (IL1R1) and tumor necrosis factor receptor superfamily member 1 A (TNFRSF1A) in the mice tissues, ameliorating apoptosis and inflammatory processes associated with nicotine-induced cardiotoxicity. This study provides a model for understanding nicotine-induced myocardial injury during experimentally transplantable neoplasm. It highlights C. vulgaris as a beneficial food supplement for cancer patients exposed to nicotine orally.

S100A6 Activates Kupffer Cells via the p-P38 and p-JNK Pathways to Induce Inflammation, Mononuclear/macrophage Infiltration Sterile Liver Injury in Mice

Noninfectious liver injury, including the effects of chemical material, drugs and diet, is a major cause of liver diseases worldwide. In chemical and drugs-induced liver injury, innate inflammatory responses are mediated by extracellular danger signals. The S100 protein can act as danger signals, which can promote the migration and chemotaxis of immune cells, promote the release of various inflammatory cytokines, and regulate the body's inflammatory and immune responses. However, the role of S100A6 in inflammatory response in chemical and drugs-induced sterile liver injury remains unclear. We constructed the model of sterile liver injury induced by carbon tetrachloride (CCl₄)/Paracetamol (APAP) and performed RNA sequencing (RNA-seq) on the liver tissues after injury (days 2 and 5). We analyzed inflammatory protein secretion in the liver tissue supernatant by enzyme-linked immunosorbent assay (ELISA), determined the inflammation response by bioinformatic analysis during sterile liver injury, and assessed mononuclear/macrophage infiltration by immunohistochemistry and flow cytometry. Immunohistochemistry was used to analyze the location of S100A6. We conducted inflammatory factor expression analysis and molecular mechanistic studies in Kupffer cells (KCs) induced by S100A6 using quantitative reverse transcription-polymerase chain reaction (qRT-PCR), ELISA, and western blot in vitro experiments. We performed chemokine CCL2 expression analysis and molecular mechanism studies using the same method. We used a Transwell assay to show the infiltration of mononuclear/macrophage. We here observed that aggravated inflammatory response was shown in CCl₄ and APAP-administrated mice, as evidenced by enhanced production of inflammatory cytokines (TNF-α, IL-1β), and elevated mononuclear/macrophage infiltration and activation of immunity. The expression of S100A6 was significantly increased on day 2 after sterile liver injury, which is primarily produced by injured liver cells. Mechanistic studies established that S100A6 activates Kupffer cells (KCs) via the p-P38, p-JNK and P65 pathways to induce inflammation in vitro. Furthermore, TNF-α can stimulate liver cells via the p-P38 and p-JNK pathways to produce CCL2 and promote the infiltration of mononuclear/macrophage. In summary, we showed that S100A6 plays an important role in regulating inflammation, thus influencing sterile liver injury. Our findings provide novel evidence that S100A6 can as a danger signal that contributes to pro-inflammatory activation through p-P38 and p-JNK pathways in CCl₄ and APAP-induced sterile liver injury in mice. In addition, the inflammatory factor TNF-α induces a large amount of CCL2 production in normal liver cells surrounding the injured area through a paracrine action, which is chemotactic for blood mononuclear/macrophage infiltration.

KRIT1: A Traffic Warden at the Busy Crossroads Between Redox Signaling and the Pathogenesis of Cerebral Cavernous Malformation Disease

Significance: KRIT1 (Krev interaction trapped 1) is a scaffolding protein that plays a critical role in vascular morphogenesis and homeostasis. Its loss-of-function has been unequivocally associated with the pathogenesis of Cerebral Cavernous Malformation (CCM), a major cerebrovascular disease of genetic origin characterized by defective endothelial cell-cell adhesion and ensuing structural alterations and hyperpermeability in brain capillaries. KRIT1 contributes to the maintenance of endothelial barrier function by stabilizing the integrity of adherens junctions and inhibiting the formation of actin stress fibers. Recent Advances: Among the multiple regulatory mechanisms proposed so far, significant evidence accumulated over the past decade has clearly shown that the role of KRIT1 in the stability of endothelial barriers, including the blood-brain barrier, is largely based on its involvement in the complex machinery governing cellular redox homeostasis and responses to oxidative stress and inflammation. KRIT1 loss-of-function has, indeed, been demonstrated to cause an impairment of major redox-sensitive mechanisms involved in spatiotemporal regulation of cell adhesion and signaling, which ultimately leads to decreased cell-cell junction stability and enhanced sensitivity to oxidative stress and inflammation. Critical Issues: This review explores the redox mechanisms that influence endothelial cell adhesion and barrier function, focusing on the role of KRIT1 in such mechanisms. We propose that this supports a novel model wherein redox signaling forms the common link between the various pathogenetic mechanisms and therapeutic approaches hitherto associated with CCM disease. Future Directions: A comprehensive characterization of the role of KRIT1 in redox control of endothelial barrier physiology and defense against oxy-inflammatory insults will provide valuable insights into the development of precision medicine strategies. Antioxid. Redox Signal. 38, 496-528.

Fingolimod attenuates ovalbumin-induced airway inflammation via inhibiting MAPK/ERK signaling in mice

The current study was designed to investigate the potential anti-inflammatory and antioxidant effects of fingolimod against Ovalbumin (Ova)-induced allergic airway inflammation compared to dexamethasone. Fingolimod was given (0.5 mg/kg/day, p.o.) for sensitized mice 1 h before Ova challenge from Days 19 to 24. Fingolimod significantly inhibited Ova-induced elevation of inflammatory cells and eosinophils numbers in bronchoalveolar lavage fluid (BALF) and reduced concentrations of immunoglobulin E in serum and of sphingosine-1-phosphate, interleukin (IL)-4, and IL-13 in BALF. Fingolimod inhibited microvascular leakage and edema as reflected by the decreased lung/body weight index. These findings were supported by histopathological examination results showing that fingolimod substantially decreased perivascular edema and inflammatory cell infiltration. Fingolimod also attenuated Ova-induced oxidative stress as evidenced by decreased malondialdehyde concentration along with increasing concentrations of reduced glutathione and superoxide dismutase in lung tissues. Fingolimod also significantly decreased monocyte chemoattractant protein-1 (MCP-1), p-ERK, and p-P38 in lung tissues of Ova-challenged mice. In conclusion, the current study demonstrated the anti-inflammatory and antioxidant effects of fingolimod in allergic airway inflammation that might be associated with the downregulation of mitogen activated kinases signaling to decrease T helper 2 cytokine secretion (IL-4 and IL-13) and MCP-1 expression, along with the inhibition of oxidative stress.

Tiron Has Negative Effects on Osteogenic Differentiation via Mitochondrial Dysfunction in Human Periosteum-Derived Cells

Tiron is a potent antioxidant that counters the pathological effects of reactive oxygen species (ROS) production due to oxidative stress in various cell types. We examined the effects of tiron on mitochondrial function and osteoblastic differentiation in human periosteum-derived cells (hPDCs). Tiron increased mitochondrial activity and decreased senescence-associated β-galactosidase activity in hPDCs; however, it had a detrimental effect on osteoblastic differentiation by reducing alkaline phosphatase (ALP) activity and alizarin red-positive mineralization, regardless of H₂O₂ treatment. Osteoblast-differentiating hPDCs displayed increased ROS production compared with non-differentiating hPDCs, and treatment with tiron reduced ROS production in the differentiating cells. Antioxidants decreased the rates of oxygen consumption and ATP production, which are increased in hPDCs during osteoblastic differentiation. In addition, treatment with tiron reduced the levels of most mitochondrial proteins, which are increased in hPDCs during culture in osteogenic induction medium. These results suggest that tiron exerts negative effects on the osteoblastic differentiation of hPDCs by causing mitochondrial dysfunction.

Toxicological effects of traffic-related air pollution on the lungs: Evidence, biomarkers and intervention

BACKGROUND

Numerous epidemiological studies have recently observed that exposure to traffic-related air pollution (TRAP) is associated with increased risk of various respiratory diseases. Major gaps in knowledge remain regarding the toxicological effects.

OBJECTIVES

We examined the toxicological effects of the gasoline exhaust particles (GEP), a paradigm of TRAP, in rats, with an objective to provide the evidence, obtain the biomarkers, and suggest effective intervention measure.

METHODS

We measured the airway hyperresponsiveness (AHR), inflammatory cells in the bronchoalveolar lavage (BAL) fluid, histological changes in the lung tissues, and the biomarkers so as to systematically examine the toxicological effects of GEPs at different dose levels (0.5, 2.5, 5 mg/kg BW). The intervention of vitamin E (VE), a natural antioxidant, on the toxicological effects was investigated.

RESULTS

The lung injury caused by GEP exposure was first indicated by the airway hyperresponsiveness (AHR). Compared with the control group, GEP exposure significantly increased the airway resistances and decreased the lung compliance; the higher the dose of GEP, the more serious the lung injury. Lung injury was also revealed by the increase of inflammatory cells, including the lymphocytes and neutrophils, in the BAL fluid. With the increase of GEP dose, histological changes in the lung tissues were further observed: inflammatory cell infiltration increased and alveolar wall thickened. The toxicology of GEP was demonstrated by the increase of the biomarkers of the oxidative stress, the pro-inflammatory cytokines and the apoptosis cytokine. However, administration of VE was found to be effective in restoring airway injury.

CONCLUSION

The toxicological effects of traffic-related air pollution (TRAP) on rat lungs are supported by evidence and biomarkers, and vitamin E intervention is feasible.

Dietary phenolic-type Nrf2-activators: implications in the control of toxin-induced hepatic disorders

Numerous studies have exemplified the importance of nuclear factor erythroid 2-related factor 2 (Nrf2) activation in the alleviation of toxin-induced hepatic disorders primarily through eliminating oxidative stress. Whereafter, increasingly more efforts have been contributed to finding Nrf2-activators, especially from dietary polyphenols. The present review summarized the phenolic-type Nrf2-activators published in the past few decades, analyzed their effectiveness based on their structural characteristics and outlined their related mechanisms. It turns out that flavonoids are the largest group of phenolic-type Nrf2-activators, followed by nonflavonoids and phenolic acids. When counting on subgroups, the top three types are flavonols, flavones, and hydroxycinnamic acids, with curcuminoids having the highest effective doses. Moreover, most polyphenols work through the phosphorylation of Nrf2. Besides, mitogen-activated protein kinases (MAPKs) and protein kinase B (Akt) are the frequent targets of these Nrf2-activators, which indirectly mediate the behavior of Nrf2. However, current data are not sufficient to conclude any structure-activity relationship.

AKAP12 ameliorates liver injury via targeting PI3K/AKT/PCSK6 pathway

A kinase anchor protein 12（AKAP12）is a scaffold protein that is critical for cell structure maintenance and signal transduction. However, the role of AKAP12 in liver injury remains unclear. Here, we attempt to explore the potential contribution of AKAP12 in liver injury and elucidate its underlying molecular mechanism. We found that AKAP12 deletion in acute liver injury (ALI) activates the PI3K/AKT phosphorylation signaling pathway, induces the increased expression of PCSK6 and its downstream inflammation-related genes, and prompts macrophages to produce a large number of inflammatory factors. And knockdown of PCSK6 by in vivo siRNA assay reversed in liver injury AKAP12^Δhep mice, demonstrating that PCSK6 has an important role in ALI. Furthermore, we found that signal transducer and activator of transcription 3 (STAT3) and serine/threonine kinase Akt (AKT) were upregulated in AKAP12^Δhep mice of chronic liver injury. To sum up, our study here demonstrates that AKAP12 has a protective role in ALI and chronic liver fibrosis, at least in part through inhibition of the PI3K/AKT/PCSK6 pathway. Our findings provide a new potential treatment for liver injury with important clinical implications.

•

The PI3K-AKT pathway is activated in the liver of AKAP12^Δhep mice upon ALI.

•

Increased PCSK6 expression is the main cause of aggravated ALI in AKAP12^Δhep mice.

•

Increased phosphorylation levels of STAT3 and AKT promote liver fibrosis in AKAP12^Δhep mice.

•

AKAP12 ameliorates liver injury through reprogramming PI3K/AKT/PCSK6 pathway.

Procyanidin B2 Attenuates Nicotine-Induced Hepatocyte Pyroptosis through a PPARγ-Dependent Mechanism

Procyanidin B2 (PCB2), a natural flavonoid, has been demonstrated to exert anti-oxidation and anti-inflammatory effects on hepatic diseases. Increasing evidence shows the hepatoxicity of nicotine. However, whether PCB2 protects against nicotine-induced hepatoxicity and the underlying mechanisms remains uncharacterized. Here, we reported that nicotine promoted hepatocyte pyroptosis, as evidenced by the elevation of propidium iodide (PI)-positive cells, the activation of Caspase-1 and gasdermin D (GSDMD), the enhanced expression of NOD-like receptor containing pyrin domain 3 (NLRP3) and the increased release of lactate dehydrogenase (LDH), interleukin (IL)-1β and IL-18. The silencing of GSDMD by small interfering RNA (siRNA) efficiently inhibited the release of LDH and the secretion of IL-1β and IL-18. In addition, rosiglitazone (RGZ) prevented hepatocyte pyroptosis induced by nicotine. Furthermore, we showed that PCB2 attenuated nicotine-induced pyroptosis through the activation of peroxisome proliferator-activated receptor-γ (PPARγ) in hepatocytes. Moreover, administration of PCB2 ameliorated liver injury and hepatocyte pyroptosis in nicotine-treated mice. Hence, our findings demonstrated that PCB2 attenuated pyroptosis and liver damage in a PPARγ-dependent manner. Our results suggest a new mechanism by which PCB2 exerts its liver protective effects.

Protective effects of propolis extract against nicotine-evoked pulmonary and hepatic damage

There is increasing interest in the use of natural products to treat many diseases, considering the minimal toxicity, availability, and low cost. Propolis, a natural resinous product produced by honeybees, has been proven for its antioxidant and anti-inflammatory properties. Therefore, this study was designed to investigate the protective potential of propolis extract against nicotine-induced pulmonary and hepatic damage in rats. Sprague Dawley rats were divided into six groups: control, propolis (200 and 300 mg/kg, p.o.), nicotine (10 mg/kg, i.p), and nicotine plus propolis-treated groups. Nicotine and propolis were given every day for 8 weeks. Then, blood and bronchoalveolar lavage fluid (BALF) were collected for assessing liver and lung functions. Liver and lung tissues were also harvested to assess oxidative stress and inflammatory biomarkers in addition to histopathological and immunohistochemical analysis. Both doses of propolis significantly decreased AST, ALT, ALP, and total and differential cell counts in a dose-dependent manner. Propolis extract significantly attenuated oxidative stress in both lung and liver tissues. The restoration of antioxidant status (GSH level, SOD activities) and reduction of nitric oxide and MDA content was more so in propolis 300-treated than propolis 200-treated group. This was parallel to the improvement seen in histopathological examination. Propolis 200 and 300 significantly decreased Nrf2 expression and increased HO-1 expression in a dose-dependent manner. Moreover, immunohistochemical examination revealed that propolis 200 and 300 decreased the expression of iNOS in lung and liver tissues while decreased TNF-α expression in lung tissues only. Propolis extract could have a protective potential against nicotine-induced pulmonary and hepatic damage via activating Nrf2/HO-1 signaling.

Pomegranate extract ameliorates renal ischemia/reperfusion injury in rats via suppressing NF-κB pathway

Inflammation and oxidative stress are the major pathways involved in ischemia-reperfusion (I/R)-induced renal injury. This study was designed to evaluate the potential effect of pomegranate against I/R-induced renal injury. I/R injury was induced in nephrectomized rats by unilateral occlusion of the left renal pedicle for 45 min followed by 24 h of perfusion. Pomegranate succeeded to decrease serum levels of creatinine, potassium, and urea nitrogen, along with increasing creatinine clearance. Pomegranate also decreased I/R-induced changes in histopathological examination. Pomegranate attenuated the renal inflammatory response reflected by the suppression of nuclear factor κB p65 DNA binding activity, the upregulation of inhibitory protein kappa B-alpha mRNA expression, the downregulation of mRNA and protein expression of tumor necrosis factor α, in addition to the reduced myeloperoxidase activity and mRNA expression. Additionally, pomegranate attenuated oxidative stress likely through the modulation of lipid peroxidation and antioxidant levels reflected by the decreased MDA content and the increased glutathione level and superoxide dismutase activity. Results confirm the potential protective effect of pomegranate against I/R-induced renal injury through its anti-inflammatory and anti-oxidant effects mediated through the upregulation of inhibitory protein kappa B-alpha, the inhibition of NF-κB activity, and the associated TNF-α release, neutrophil infiltration, and oxidative stress.

Metformin attenuates H2O2-induced osteoblast apoptosis by regulating SIRT3 via the PI3K/AKT pathway

Osteoporosis is a common metabolic disease that has a high incidence in postmenopausal women. Studies have indicated that oxidative damage plays an important role in the development of postmenopausal osteoporosis. Metformin has been showed to have the ability to relieve excessive oxidation. The aim of the present was to determine the therapeutic effect and potential mechanism of metformin in postmenopausal osteoporosis. Oxidative damage was stimulated in vitro by the addition of H₂O₂ to MC3T3-E1 cells and a mouse menopausal model was also constructed. Cell viability and flow cytometry experiments were performed to determine the effects of H₂O₂ and metformin treatment on apoptosis. Mitochondrial membrane potential was tested by JC-1 assays. Western blotting was used to detect the expression of mitochondrial apoptosis markers and antioxidant enzymes. Small interfering RNA was used to knockdown sirtuin3 (SIRT3), which was verified at the mRNA and protein levels. Bilateral ovariectomy was used to prepare menopausal mice, which were analyzed using micro-computed tomography. The results indicated that metformin is able to repair mitochondrial damage and inhibit the apoptosis of osteoblasts induced by H₂O₂, and also reverse bone mass loss in ovariectomized mice. Western blotting results demonstrated the involvement of SIRT3 in the production of antioxidant enzymes that are essential in protecting against mitochondrial injury. In addition, experiments with SIRT3 knockdown indicated that metformin reverses H₂O₂-induced osteoblast apoptosis by upregulating the expression of SIRT3 via the PI3K/AKT pathway. The results of the present reveal the pathogenesis of oxidative damage and the therapeutic effect of metformin in postmenopausal osteoporosis. They also suggest that SIRT3 is a potential drug target in the treatment of osteoporosis, with metformin being a candidate drug for modification and/or clinical application.

Diminished CCl4 -induced hepatocellular carcinoma, oxidative stress, and apoptosis by co-administration of curcumin or selenium in mice

Hepatocellular carcinoma (HCC) is a lethal disease, and in HCC advanced stages, there is limited therapeutic efficacy. HCC results in a complication of fibrosis or cirrhosis. In this study, the protective effect of curcumin and selenium versus hepatocellular carcinoma caused by CCl₄ in experimental animals was investigated. In all, 70 mice were divided into seven groups to study the effect of curcumin and selenium on CCl₄ -induced hepatocellular carcinoma. After treatment time, different animal groups were sacrificed, serum and liver samples were collected and processed for assay of biochemical and molecular parameters. Our results showed that CCl₄ administration induced various alterations such as significant elevation in the serum levels of ALT, AST, and hepatic contents of malondialdehyde (MDA), and depletion in the levels of antioxidant parameters. CCl₄ induced apoptosis in the hepatic cells indicated by an increased level of p53, CD4, CD8, Bax, and Annexin V/PI in addition to significant decrease in the level of Bcl-2. Administration of curcumin and selenium restored this abnormal variation in these biochemical parameters to normal values. Our study addressed that curcumin or selenium may be helpful in the protection against liver damage induced by CCl₄ . The hepatoprotective impact of curcumin or selenium might be mediated primarily by its potent antioxidant activity. PRACTICAL APPLICATIONS: Hepatocellular carcinoma (HCC) ranked third common cause of death, primary liver cancer. Exposure to CCl₄ was found to induce significant hepatotoxicity, characterized by fibrosis, bile duct proliferation, cirrhosis, and reduced hepatic function The work was prepared to investigate the protecting capacity of curcumin, selenium alone, and in combination against HCC induced by CCl₄ in the experimental animal model. This study proved the protective effect of curcumin and selenium, alone and in combination with each other, where curcumin showed multiple pharmacological activities, including anti-inflammation and antioxidant, and have an essential role in inhibiting the progression of HCC.